NP-229 Xfer Case Operation

[TPIGUY]

Guys,

I found this forum the day after I bought my (impulse buy) 85 GW. After reading about the front timing cover problems and the NP-229 case, I thought, what have I done now. Oh well, I got a 4 door SUV and A/C for $1200. The rest is gravy. Anyway, can anyone tell me what an NP-229 case is? Full time front wheel drive and part time makes no sense to me with no way to lock the hubs. If my front drive shaft is always turning can I remove it to save gas? I don't need 4WD at all. Thanks.

[scotty]

the 229 has a 2wd,a full time 4wd,neutral,and a low range that is locked like a conventional part time case. the high range full time 4wd does not lock the front/rear driveshafts like a conventional part time case,it uses a silicone filled viscuous coupling center differential to control front/rear slippage and still allow the front and rear wheels to turn at different speeds on pavement,without fear of binding or breakage.
you can install lockouts,or remove the front driveshaft in 2wd,as long as you are aware that trying to drive in high range 4wd with hubs unlocked,or driveshaft missing,will damage the expensive viscuous coupling,so make real sure that you dont accidentally do it. the thing to worry about is that when the viscuous coupling goes bad,alot of times the vehicle will no longer move in 2wd,due to the way the 229s internals create 2wd. all power will go to the driveshaft with least resistance(just like any open differential) and all power will spin out the not connected front output. you will have to have the front driveshaft to be able to move,or hope you are close enough to home to be able to get there in 4lo. the spinning front driveshaft is probably not robbing you of much fuel economy. make sure youre engine is in tune,with no vaccum leaks,and you might try synthetic lubricants.ive heard as much as 2-3 mpg increase with synthetic lubes. if you do want a non spinning driveshaft,id install soe lockouts. now the front diff wont turn,and all you have to do if you have t case problems s simply lock the hubs. just make sure you lock them every now and then ad drive a couple miles to keep everything lubed. if you opt to simply remove the shaft,id carry it with you,and the tools to install it,just in case.

hope this answers your questions...

------------------
scott
85 grand wagoneer
258/904/twin stick dana 300/dana 44/welded amc 20
38x15.5 gumbo mudders
snorkel/dual batteries/onboard air/"custom" convertable
3 inch body lift/mostly stock suspension/"modified" fender openings
custom front/rear bumpers and brushgaurd

[joe]

I personally don't think pulling the front shaft or adding manual hubs is worth the time/money and risk. As Scotty mentioned if you, your wife, bro-in-law, kid, whoever did pull it into 4WD with the shaft removed or hubs locked..."Poof" goes the viscous coupler. Somewhere I believe around $200-$300 just for the part if you can still even get one.
So far as gas mileage goes I doubt you'll see any improvement. The 83 and 84 Wags had a vacuum disconneted front axle in them to keep the front axle and driveshaft from spinning in 2WD. Same result as manual hubs but it was sorta idiot proof because the axle was run from the same vac switch that controls 2WD/4WD so you couldn't accidently go into 4WD w/o the front axle engaging. This was of course assuming the actuator on the axle is working properly and you have no vacuum leaks in the rotted hose going to it. Bottom line is that I'm not aware of the 83/84 getting one bit better gas mileage than the later or even earlier Wags. Prolly why AMC dropped the vac axle after two years. Keep in mind these things have a curb weight of roughly 4800lb with a driver and a full tank of gas. It's gonna take some fuel to move'm. Especially with their fine aerodynamics http://www.cs.colostate.edu/~zeimet/ubb/smile.gif
If gas mileage is a big concern to you or your family...you're driving the wrong vehicle.

-joe

[TPIGUY]

Ok now I'm really scared. Sounds like a freshly hired NASA engineer made a wrong turn and went to Detroit instead of Florida. A silicon filled viscous coupled center diferential? Didn't they leave that on the moon back in the 70s? Ok, let me ask a simpler question. If I leave it in 2WD forever, will the front drive shaft be turning? Thats all I really need to know cause if it doesn't turn, that 2WD to 4WD switch on the dash is going to get a new label called DANGER FIRE ALARM.

[joe]

Nothin to be scared of at all so long as you leave the drive shaft in place and/or don't install manual hubs.
Yeah in stock form the shaft will be turning in 2WD but I wouldn't worry about it.
The 229 isn't a bad x-case at all, better than the 228 and 219 full-time x-cases. Since you don't have the vac front axle you don't have to worry about an acuator or vac hose not working and causing the VC to grenade when going into 4WD. With the 85 and up that you have don't worry about a hose leaking etc. If that happens it just won't go into 4WD but won't hurt anything.
Since you seem not to be too concerned with using 4WD and some day if the 229 does go south, you might consider replacing it with a conventional NP208 part-time x-case(cheaper too). With that case the 2WD/4WD is controlled by a regular shift lever as on older 4x4's. Also with that x-case you can add manual hubs and if you do forget to lock them you just won't have 4WD till you do but here also you won't hurt anything.
Personally if your 229 is working fine the way it is I'd leave it alone. It's one of those "if it ain't broke, don't fix it" things or you may end up subscribing to the theory of "if it ain't broke, fix it till it is" http://www.cs.colostate.edu/~zeimet/ubb/smile.gif
-joe

[Puvong]

<BLOCKQUOTE>quote:</font><HR>Originally posted by TPIGUY:
Guys,

I found this forum the day after I bought my (impulse buy) 85 GW. After reading about the front timing cover problems and the NP-229 case, I thought, what have I done now. Oh well, I got a 4 door SUV and A/C for $1200. The rest is gravy. Anyway, can anyone tell me what an NP-229 case is? Full time front wheel drive and part time makes no sense to me with no way to lock the hubs. If my front drive shaft is always turning can I remove it to save gas? I don't need 4WD at all. Thanks.<HR></BLOCKQUOTE>


The NP208 part-time Xcase will not solve your
problem, because the front driveshaft/axle are still turning whenever you move. I have the NP208 on my 80-Cher,and I get between 10 to 13-mpg average depending on the day?. I don't think it will worth to disconnect the front driveshaft to save the gas, because these ugly creature's weight are too much. Yes, I am also concerning about the gas mileage too, but what else I can do beside a proper maintenances on the truck because I don't have X-$$$$ to spend on $$$$ after market parts.

[joe]

Your front shaft is still turning in 2WD?
The 208 x-case equipped vehicles came with manual hubs as standard equip. If you have the hubs unlocked and the front shaft is still turning, which means the front axle is too...what's the purpose of the unlocking hubs???? It will turn the axle and shaft if the hubs are locked though.
Somethings not right here...or your hubs are locked in.
Do do have locking hubs on your 1980 right? If not you prolly don't have the 208 but the 219 full-time case.
What's the shift pattern on the shifter? If it has a "LOCK" position it's the 219 full-time x-case. The 208 just has 2H-4H-N-4L. The 219 has 4L-N-4H-LOCK.
-joe

[Puvong]

[The 208 x-case equipped vehicles came with manual hubs as standard equip.
what's the purpose of the unlocking hubs???? It will turn the axle and shaft if the hubs are locked though.
Somethings not right here\
. The 208 just has 2H-4H-N-4L. The 219 has 4L-N-4H-LOCK.


Sorry Joe, may be some confusions here?. I admit that I'm no expert on FSj's Xcase. Yes,I have a manual hub which will provide an option to engage 4WD when locked.
However, the driveshaft/axle are still turning if the hubs are unlocked.
My 80-Che has 4H-N-4L on the shifter, which explans the front driveshaft/axle are turning
all the time.
I wish the FSJ came with the Select-trac xcase as on a late model Jeep which provides
an option to engage 2WD/4H part-time/4WD full-time/N/4L.

[scotty]

you could install a conventional 2wd tranny,and single driveshaft to rear wheels,but that would make the jeep gods very,very angry. http://www.cs.colostate.edu/~zeimet/ubb/mad.gif my heart aches for the poor souls who have never experienced the fun that is possible to be had with a properly functionaing 4 wheel drive vehicle. http://www.cs.colostate.edu/~zeimet/ubb/frown.gif

anyway, as to whats better,welllll, i guess that that depends on your definition of better. the 228 is just like the 229,but with an open center diff instead of a viscuous coupling. i guess that the 229 could be better,since the viscuous coupling controls slippage(a limited slip fo xfer case http://www.cs.colostate.edu/~zeimet/ubb/biggrin.gif )but,i guess that the simplicity of an open diff could be considered better,too-you dont often hear of the center diff going out on a 228... it is however,prone to the other problems that plague the 229-the shift actuator,and cracking case halves.and you still cant limp home on the front driveshaft unless home is close enough to get there in 4 lo. if you mean better meaning "less likely to break" id probably disagree there. id say 6 of one,half a dozen of the other,as far as reliability goes. if a persons intent is off road abuse,they are both worthless. as for street the VC is nice for "inclimate weather driving."

the 219 is a good case-unless 2wd is for some reason an important factor-this is its only real disadvantage. you have a full time 4wd,and a high lock,and low lock. i wheeled a 219 for about 2 years and beat it unmercilessly.(gawd,that cant be spelled right) i drove it several times in hi lock with the rear driveshaft removed. driving on the road in full time 4wd never bothered me,until i started using it in my GW-then it caused alittle extra vibration since my front driveshaft was a crooked,"home shortened" mess. i quit using it when the chain started slipping,which of coures is the biggest problem with any full time case-the chain is always used and stretches. i swapped in a 207 in its place. i fully intend to replace the chain and continue to use it in another project vehicle. i would personally much rather have a 219 than a 228 or 229 for street or off road use. you have one simple shifter-no funky vaccum actuator to worry about.its also more reliable,and will still get you home if you have to remove your rear driveshaft.

if you like 2wd,full time 4wd,and a high lock option,i think the 242 swap is a neat idea.(i get confused by all the names-command trac,selec trac-i wish everyone would simply refer to new process cases by their numbers). it looks to be about the same length,and it will bolt to your existing tranny. it has a slip yoke intead of a fixed rear yoke,so youll need a new driveshaft,and youll need to make/borrow a shifter,i dont think the plastic flag deal can be made to work with the 5 position shift pattern. the shifter from xj cherokee that the 242 will probably come from can probably be made to work. in something thats nice,and used to drive the family around,and taken for occasional off road adventures to camp or fish,i think the 242 would be a cool addition to a full size.

last,and not least,i agree completely with joe-if it aint broke-dont fix it. the fact that the front driveshaft spins is not taking much,if any,fuel economy away. change the fluid at regualr intervals(this goes for the tranny too) and dont worry about it. if you ever have any trouble with it,it is easy to swap the new process cases around,so youll never have to worry about not finding SOMETHING that will work.



------------------
scott
85 grand wagoneer
258/904/twin stick dana 300/dana 44/welded amc 20
38x15.5 gumbo mudders
snorkel/dual batteries/onboard air/"custom" convertable
3 inch body lift/mostly stock suspension/"modified" fender openings
custom front/rear bumpers and brushgaurd

[joe]

<BLOCKQUOTE>quote:</font><HR>Originally posted by Puvong:
[Sorry Joe, may be some confusions here?. I admit that I'm no expert on FSj's Xcase. Yes,I have a manual hub which will provide an option to engage 4WD when locked.
However, the driveshaft/axle are still turning if the hubs are unlocked.
My 80-Che has 4H-N-4L on the shifter, which explans the front driveshaft/axle are turning
all the time.
<HR></BLOCKQUOTE>

Puvong, not to be sorry, I'm no expert either but between you, me and possibly a few others we'll stumble through this http://www.cs.colostate.edu/~zeimet/ubb/smile.gif
First unless it's a typo you wrote...you're missing a "2H" position on your shift lever. All 208's have a 2WD(hi) position. It's either forward or aft of the 4H position depending if you have a manual or AT.
Moving the lever forward with the manual trans the pattern is 4L-N-4H-2H. With the AT moving forward the pattern is 2H-4H-N-4L.
You say yours has only 4H-N-4L???? Is that a typo or what happened to the 2H slot? Indeed if you are in 4H or 4L the drive shaft will move even with the hubs unlocked but that ain't s'posed to happen cause you need to get into 2H for the driveshaft not to turn. It still will turn in 2H if the hubs are locked but then it's being turned by the tires/axle not by the x-case as in 4H/4L.
"ALL part-time" transfer cases have a 2H position if it's a two speed(H/L). Even all single speeds have a 2WD spot, at least all used in Jeeps do...can't say about AWD Subaru's, Audi's etc but who cares about those anyway http://www.cs.colostate.edu/~zeimet/ubb/wink.gif
Something here is still amiss...Where's your 2H positon?
Either you need to shove/pull (depending on trans) harder/farther to get from 4H to 2H? Shift knob is worn where you can't read the 2H position?
Maybe you actually are in 2H but your hubs are frozen/rusted/gummed up etc and turning the selector isn't unlocking them?
Almost last but not least guess is you're still missing a position on the shift lever "LOCK" but that means you have a 219 full-time x-case (no manual hubs) and yes the shaft will turn all the time no matter what.
Very last and maybe least guess is you have the full-time 219 and someone installed manual hubs on your rig??(not stock and useless).

Anyone else have any ideas here to help Puvong find his missing 2H slot? The 208 really did come with 2H from the factory Puvong...honest http://www.cs.colostate.edu/~zeimet/ubb/smile.gif

-joe

[joe]

Puvong, going back over your earlier post I'm thinking maybe you and I are confused regarding the "locking the hubs" and "locking the axles together via the x-case lever".
Do your hubs have a twist selector(at each front wheel) that reads 2WD/4WD drive(manual hubs)?
When you refer to "locked" do you mean by getting out of the Jeep and turning each selector at each front wheel or by moving the shift lever to the "lock" position inside the Jeep?
My latest guess again is that you have regular hubs which are locked all the time and don't have the selectors at each wheel to "unlock the hubs" as with manual hubs and you do have a "lock" position on your shift lever to lock the axles together via the x-case?
If this is pretty close...you have the full-time NP219 x-case and not the part-time NP208. Both were available in 1980-83.

-joe

[scotty]

hows about crawl under that sucker with a rag and rub all the grime off the little round tag that gives you the model #? that would be the easiest way i could think of.

as joe mentioned,your lockouts could be funked up and not engaging.do you have factory jeep lockouts?or some kind of aftermarket? does your shifter have the "lock" position or a "2wd" position?

if its a manual tranny,its gotta be a 208-i dont think the 219 ever came behind a manual. if the marks on the shifter are worn out,and the id tag is missing you can determine having a 2wd like this: place a rollable floor jack under the front axle,and jack 1 wheel off the ground.now put it in drive in each gear on the t case. in 2wd,or high lock the jeep will move.in full time high on a 219,the front tire that is off the ground will spin,and you will not move.this condition cannot occur with a 208,so if you can spin a front wheel with it off the ground,you definately have a np 219.

a tidbit for joe: although it is debatable weather it is a jeep,the AMC eagle used a new process 119 transfer case in 1980 and until mid 81 that was single speed,full time with no 2wd.

also,what about quadra trac? no 2wd on them,either.



------------------
scott
85 grand wagoneer
258/904/twin stick dana 300/dana 44/welded amc 20
38x15.5 gumbo mudders
snorkel/dual batteries/onboard air/"custom" convertable
3 inch body lift/mostly stock suspension/"modified" fender openings
custom front/rear bumpers and brushgaurd

[joe]

<BLOCKQUOTE>quote:</font><HR>Originally posted by scotty:

a tidbit for joe: although it is debatable weather it is a jeep,the AMC eagle used a new process 119 transfer case in 1980 and until mid 81 that was single speed,full time with no 2wd.

also,what about quadra trac? no 2wd on them,either.

<HR></BLOCKQUOTE>


Scotty, I'm aware of the single speed full-time 119 in the Eagle but that's just a single speed version of the 219 full-time x-case. The BW/QT is also a full-time case unless converted to PT.
I think(?) I said earlier "all part-time x-cases" have a 2H position. The full-time cases don't have a 2WD position...hence the tern full-time 4WD. The only odd balls here are the 228 and 229's but Jeep calls them "full-time/part-time" x-cases http://www.cs.colostate.edu/~zeimet/ubb/smile.gif
Another odd one may be the 242 also maybe being a full-time/part-time case(?) but since it was never used in FSJ's I know even less about those than I do about the FSJ x-cases which isn't much http://www.cs.colostate.edu/~zeimet/ubb/wink.gif
-joe

[Puvong]

First unless it's a typo you wrote...you're missing a "2H" position on your shift lever. All 208's have a 2WD(hi) position. AT moving forward the pattern is 2H-4H-N-4L.
what happened to the 2H slot?


Thanks Joe, I have learned something here on the NP208 Xcase. You are right, I am missing
a 2H label on the shift lever and I wish I have a photo to show you that the 2H marking is gone completely, except 4H-N-4L.
I just bought this truck about three months ago right after only two weeks that I have discovered this Web site. Here is my silly misunderstanding: When I first drove the truck before buying it, the owner told me that it had been sitting on his driveway for almost two years now, so my mind was toward more on the motor than the other things, and for some reason he left the shift lever locked on 4H and he just told me to Lock the hubs only when engaging 4WD. there is no owner's manual or any other indications that tell me whether the truck is locked in 4WD or 2WD mode neither. that's why I said the front driveshaft/axle are turning all the time. Anyway, thanks again for your time to clear this up for me.

[BobBarry]

<BLOCKQUOTE>quote:</font><HR>Originally posted by -joe:

Scotty, I'm aware of the single speed full-time 119 in the Eagle but that's just a single speed version of the 219 full-time x-case.<HR></BLOCKQUOTE>

The '63-'65 Wags with the Borg-Warner auto trans came with the Dana 21 single-speed transfer case. The thinking was that the torque-converter provided whatever gear-reduction a low-range would otherwise give (you can see how they abandoned that thinking when the TH400 came with the D20 2-spd case).

<BLOCKQUOTE>quote:</font><HR>I think(?) I said earlier "all part-time x-cases" have a 2H position. The full-time cases don't have a 2WD position...hence the tern full-time 4WD. The only odd balls here are the 228 and 229's but Jeep calls them "full-time/part-time" x-cases http://www.cs.colostate.edu/~zeimet/ubb/smile.gif
Another odd one may be the 242 also maybe being a full-time/part-time case(?)<HR></BLOCKQUOTE>

Jeep's terminology is correct: full-time or part-time refer to different MODES of 4wd, while the transfer-case is designated by the type of mode available, NOT by whether you can shift it out of 4wd or not.

So, for example, the original BW1339 Quadratrac transfer-case is actually a full-time/part-time case, just like the NP242, since it has a full-time (normal mode) 4wd option (=can drive on pavement, and thus "full-time") and a part-time (emergency-drive) 4wd option (=don't drive on pavement, only loose surfaces).

Since "full-time" cases with a 2wd mode only were introduced with the NP229 in 1983, many people still think that part-time cases are ones that have 2wd modes, and full-time cases are the ones that don't (because this was the way things were up until then).

Other times, a transfer-case is known by its primarily-used 4wd mode, rather than by all available modes. That is why an NP229 and a BW1339 are usually referred to as "full-time" cases, because the dominant 4wd mode is a full-time mode, even though other modes are available.

------------------
Bob Barry<UL TYPE=SQUARE>* '78 Cherokee 4-door
* '88 Grand Wagoneer[/list]http://studentweb.providence.edu/~rbarry/wheels/

[joe]

<BLOCKQUOTE>quote:</font><HR>Originally posted by BobBarry:
So, for example, the original BW1339 Quadratrac transfer-case is actually a full-time/part-time case, just like the NP242, since it has a full-time (normal mode) 4wd option (=can drive on pavement, and thus "full-time") and a part-time (emergency-drive) 4wd option (=don't drive on pavement, only loose surfaces).<HR></BLOCKQUOTE>

Well that's not quite correct Bob. The BW/QT is strictly a full-time transfer case. In order for a x-case to be a combo full/part-time it has to have a "2WD only" mode, hence the part-time part of the designation. In the 2WD mode no matter how much you spin the rears it's still in 2WD.
The BW/QT has no 2WD mode. Sure it runs in 2WD till the rear axle loses traction but then it kicks in the front axle, hence full-time x-case. Same senario with the full-time 219 which also has no separate 2WD mode.
The 229 does have a "2WD drive only" mode along with a 4WD mode that really runs in 2WD till the back loses traction and kicks in the front axle.
Granted the designations aren't if "you" can shift from 2WD to 4WD but rather if the x-case does it for you by losing rear traction and engaging the front axle automatically.
If if has both functions of 2WD "only" and 4WD via a limited slip connection in the x-case it's a part-time/full-time case. If it has no "strickly 2WD" mode its a full-time x-case.
That's the way Jeep describes their gear boxes anyway till the end of the FSJ's run.
What Chrysler et al are running or calling them now-a-days I don't know. I suspect the only two types of x-cases avail today are the strictly part-time cases like the 231 and the full/part-time such as the 242 which they prolly do just call a full-time case because earlier cases such as the true full-time only BW/QT, NP 219, 119 are long gone.
-joe

[TPIGUY]

Originally posted by -joe:
The 229 does have a "2WD drive only" mode along with a 4WD mode that really runs in 2WD till the back loses traction and kicks in the front axle.
Granted the designations aren't if "you" can shift from 2WD to 4WD but rather if the x-case does it for you by losing rear traction and engaging the front axle automatically.
If if has both functions of 2WD "only" and 4WD via a limited slip connection in the x-case it's a part-time/full-time case. If it has no "strickly 2WD" mode its a full-time x-case.


JOE........

This is the first time I finally understand the difference between full time/ part time cases. Now, my question is this:

If I am in "part time" 2WD mode in which only the rear axle is driven, is my front drive shaft turning? If it is turning, is it because the front wheels are driving the front axle which is in turn spinning the driveshaft? Or are the front hubs free which means the axle is being driven by the case. The problem for me is, I have never had a 4WD vehicle with automatic hubs and I really don't understand how they work.

[BobBarry]

<BLOCKQUOTE>quote:</font><HR>Originally posted by -joe:
Well that's not quite correct Bob. The BW/QT is strictly a full-time transfer case. In order for a x-case to be a combo full/part-time it has to have a "2WD only" mode, hence the part-time part of the designation.<HR></BLOCKQUOTE>

Nope. Well, not according to Jeep's use of the terms "part-time" and "full-time". These two terms are used in two different ways, and can cause confusion for newbies:

1) Proper Use of the Terms: Part-Time and Full-Time refer to 4wd modes, NOT to the transfer-case itself, according to whether you can shift out of 4wd or not.

Thus, on p.22 of the 1988 Jeep Grand Wagoneer/J10/J20 Owner's Manual, in describing the NP229 Selectrac system, it states:
<BLOCKQUOTE>quote:</font><HR>Selectrac provides:<UL TYPE=SQUARE><LI> Either 2- or full-time 4-wheel drive in HI range...
<LI> Part time four-wheel drive in LO range.[/list]<HR></BLOCKQUOTE>
Here, Full-time refers to a differentiated 4wd mode, and Part-time refers to a 4wd mode where the driveshafts are locked together. To make this point clearly, the manual describes the different modes on p.24:
<BLOCKQUOTE>quote:</font><HR><UL TYPE=SQUARE><LI> HI Position 2WD or 4WD- In either position, the vehicle may be operated on all road surfaces. In 4WD, Selec-Trac offers better traction when roads are wet, snow-covered or icy. Use Selec-Trac 4WD year-round (full time) if you wish...
<LI> L0 Position- This position provides 4WD for occassional use when off road driving conditions require low-speed pulling power[/list]<HR></BLOCKQUOTE>
So, according to Jeep's use of the terms, a full-time mode is one that provides some kind of differential between the driveshafts so the mode can be used FULL TIME. A part-time mode is one that locks the driveshafts to spinning at the same speed, and which cannot be used full time, but rather, only PART TIME, namely, that part of the time you drive the truck on
loose surfaces.

2) Not Technically correct, but nevertheless common, use of the terms: Here the adjective describes the transfer case, not a 4wd mode it uses, and refers to whether a transfer case can be shifted out of 4wd into 2wd (and thus is considered to be a "part-time" 4wd case), or whether it cannot be shifted out of 4wd (and is thus a "full-time" 4wd case). This is a common use of the term, and generally based on the primary 4wd mode the transfer-case is designed to be used in. So, according to this, a BW1339 and an NP229 are both "full-time" transfer-cases, since the 4wd mode they are usually used in (4wd Hi) differentiate the output to the driveshafts.

<BLOCKQUOTE>quote:</font><HR>Granted the designations aren't if "you" can shift from 2WD to 4WD but rather if the x-case does it for you by losing rear traction and engaging the front axle automatically.<HR></BLOCKQUOTE>

So you're saying that the presence of a differentiated 4wd mode, in which you say it runs in 2wd until traction is lost at the rear, makes the transfer-case into a "part-time" unit? Or a full-time unit?

<BLOCKQUOTE>quote:</font><HR>If if has both functions of 2WD "only" and 4WD via a limited slip connection in the x-case it's a part-time/full-time case. If it has no "strickly 2WD" mode its a full-time x-case.<HR></BLOCKQUOTE>

According to Jeep terminology (at least circa 1988- B.C., or Before Chrysler, who hadn't bought them by the time this manual went to print), the NP219 and the BW1339 would also be a full-time/part-time case, because they had both modes, even in HI range.

I'd imagine that prior to the introduction of the NP229, there was no problem of confusion in the way people used the terms, because the only tranfer-cases with the 2wd mode were the "part-time transfer cases" (i.e. NP205, NP208 and D20), and none of the available "full-time transfer cases" (i.e. NP203, NP219 or BW1339) had a 2wd mode. Cases were marketed and known by the 4wd mode they were primarily used in.

In reality, though, the NP219 and BW1339 had part-time 4wd modes, even if they weren't
marketed as full-time/part-time cases (it would be interesting to see if any factory literature refers to the NP219's "4WD-HI-Lock" mode as a part-time mode).

In most cases, this all doesn't amount to a hill of small beans. There is one important exception, however, where this confusion can lead someone astray, and that is with the part-time conversion kits for the BW1339 QT systems. Occassionally, someone will post a question about this conversion, say that they are looking for the benefits of the traction that a part-time case affords, and ask whether this conversion will give them what they're looking for out of their QT case. In fact, this conversion does not *add* a part-time 4wd mode capability to the transfer-case; rather, it simply converts the full-time 4wd mode to a 2wd mode. The part-time 4wd mode it offers is simply leaving in place the part-time 4wd mode the transfer case had when the "Emergency-Drive" is engaged (a center differential lock, in current-day terms). If a traction advantage is all a person is looking for, they can have it simply by switching a dial in their glovebox, rather than spending a few hundred on a conversion that uses the exact same setting on the switch.

------------------
Bob Barry<UL TYPE=SQUARE>* '78 Cherokee 4-door
* '88 Grand Wagoneer[/list]http://studentweb.providence.edu/~rbarry/wheels/

[joe]

<BLOCKQUOTE>quote:</font><HR>Originally posted by TPIGUY:
JOE........

This is the first time I finally understand the difference between full time/ part time cases. Now, my question is this:

If I am in "part time" 2WD mode in which only the rear axle is driven, is my front drive shaft turning? If it is turning, is it because the front wheels are driving the front axle which is in turn spinning the driveshaft? Or are the front hubs free which means the axle is being driven by the case. The problem for me is, I have never had a 4WD vehicle with automatic hubs and I really don't understand how they work.<HR></BLOCKQUOTE>

Hi TPIGUY,
First let me say you don't have "automatic hubs"...you've got just plain ole ordinary hubs that have been used since the advent of 4WD. The hubs are solid locked-in all the time as it's always been. Free wheeling/manual/unlocking or whatever you want to call them are a later invention to disconnect the wheels from the axle and were optional for years. They were standard in the late 70's up on most 4x4's but still optional on some 4WD's as CJ's etc.
Back to your question, yeah even in 2WD your front drive shaft will still turn from the wheels turning the axle, axle turning the drive shaft.
That's the case with any vehicle that has solid normal hubs. That's why they invented locking/manual/free wheeling whatever hubs, so the wheel is disconnected from the axle and saves wear in the front diff and gas mileage. They were basically for part-time transfer cases because that's all that were built at that time. It also made steering a bit easier since most 4x4's back then were built for offroad/rough road use but could be driven on the hwy...so a lot didn't have power steering.
Today's rigs are bascally for street use but can be offroaded. Since the advent of the full-time and the later full/part-time x-cases hubs are really no longer needed and in some cases detremental(sp?) to a x-case.
Example is a BW/QT full-time case without the part-time conversion kit. If you ran manual/selective hubs on it and had the wheels unlocked and driving you'd burn up the x-case because the wheels turning the axles turning the front drive shaft provide required lubrication for the front of the x-case.
That's not the case though with your 229. You can add manual hubs to yours. You don't need the front shaft turning to lube the x-case but as mentioned earlier you DO run the risk of the 229 being put in 4WD with the hubs unlocked and blowing the viscous coupler in it.
If you went out and spent $150 on a good set of Warn Premium hubs I'd really be surprised if you got a 2 mpg gain. Prolly one but two is unlikely. I've owned mostly older 4x4s and some didn't come with manual hubs that I did convert and I never "in real life" never saw any significant gains. Opps, I did on one rig. I bought a brand spanking new FJ-40 Lancruiser in 1978 and added manual hubs and I did get a 2 mpg gain but to do that on a 100,000+ mile rig with 100,000+ wear on the engine and drive train?...been there, done that and didn't really get a noticable gain.
Save your money and save yourself the anxiety of the possibilty of the lady of the house putting it in 4WD on a slick road with the hubs unlocked http://www.cs.colostate.edu/~zeimet/ubb/wink.gif
-joe

[River Beast]

Bobbarry,

I think you confused two separate cases by mistake... The BW1339 is a QUADRATRAC....TOTALLY different animal than the Selectrack. Speaking from the BW1339 knowledge that I have gained since ownership, is a FULL-TIME 4WD. there is no part-time... no shifter at all (E-Drive is NOT a part-time operation... explained below), except those with a 2:56:1 low range reduction unit. The front and rear output shafts ar connected thru a limited- slip style center differential inside the QT. I know this becasue I have rebuilt 3 of them to date. The center diff works off of pressure applied to the center diff thru brake cones. Power is then transferred to the front and rear axle repectively. The drawback to the center diff is this: it actually will transfer power to the least resistance axle at times of severe traction loss. That's where the E-drive comes into play. There is a vaccum acutated plunger that moves a coupling ring onto the rear of the center diff inside the QT to "lock" the front and rear output shafts together and provide a 100% transfer of power split 50% to the front and 50% to the rear. This is why there were no manual hubs on the rigs equipped with the BW1339 QT. If you were to have access to a manual for the QT it tells you not to install them because severe damage would be caused to the QT. If you were to remove the front driveshaft on a rig with a QT (or installed manual hubs and unlocked them)and tried to drive without the E-drive actuated... you ain't going nowhere!!! The power would all be transferred to the front (least resistance)...
Ask Porkchop... he found out the hard way... http://www.cs.colostate.edu/~zeimet/ubb/Forum2/HTML/000626.html

I hope this sums up the confusion some....

------------------
TJ
78 Wagoneer "River Beast"
360/TH400/QT
Dana 44's (soon to be 4.88's)
7" SOA conversion
4" Skyjacker Softride
3" Trailmaster Bodylift
33x12.50's on 15x10's
(soon 38.5x14.50's on 12's)
My FSJ site: http://www.geocities.com/~spazz4life (http://www.geocities.com/~spazz4life)
"Where there's a hill...there's a way!"



[This message has been edited by River Beast (edited July 28, 2000).]

[joe]

[QUOTE]Originally posted by BobBarry:
[B]

Bob, sorry for snipping the above but this is getting way too hard for me to edit line by line.
From memory here...
You quoted the 88 Chrysler manual on PT and FT cases. For one thing by 88 when DC actually was in the Jeep business there were no PT cases in FSJs. The 208 was dropped in 87.
I agree that the old time definition of PT meant that 4WD can only be used PT as on low traction sufaces. But FT's can be used on dry pavement in 4WD mode.
But the old terms also apply to PT having a 2WD mode which neither the 1339 or 219 have.
According to AMC from AMC factory shop manuals the BW1306/1339 QT is a FT case. The NP219 is a FT case. The 229 is a PT/FT case. Now if Chrysler wants to change the lingo(after the 219 and BW/QT don't even exist anymore) on what AMC called their stuff I guess it's ok since it's their company now. They could call AMC Red blue now if they choose but that doesn't change the fact it's still AMC Red according to AMC http://www.cs.colostate.edu/~zeimet/ubb/smile.gif
I do agree with you that by todays/Chryslers and maybe others definition the BW/QT might be called a part/full-time case but AMC never did nor did Borg-Warner. Even the NP219 which was built by Chrysler(? NP?) is called a "full-time" case by their own definitions. Does it also fall into Chryslers new PT/FT catagory? It hasn't been in a Jeep for 5 years before Chrysler built Jeeps. I really think that Chryslers 88 to present definitons apply to whats being built by them at the time and not to x-cases others have used or built long before they bought Jeep.
What you've said Bob makes perfectly good sense and I agree but my only point is that BC the terms don't match Chryslers of what's PT or FT or both. I go by what the terms were when the stuff was built/used. Which DC seems to be doing also with the new stuff. Guess I may have to learn all new terms huh? http://www.cs.colostate.edu/~zeimet/ubb/smile.gif
Nahhh...I'll never own a Chrysler designed Jeep anyway. Maybe one built by'em but not designed by'em.
It's late Bob...if ya wanna continue this lets do it by email tomorrow or start a new labled thread like "was 229". Besides the editing the scrolling is way long http://www.cs.colostate.edu/~zeimet/ubb/smile.gif
I'll also get back to ya on the 192/162/161? F/L head, six cyl stuff from the 1FSJ list tomorrow via email. Need to pick your brain on this odd ball engine stuff.
Good night,
-joe

[BobBarry]

<BLOCKQUOTE>quote:</font><HR>Originally posted by River Beast:
Bobbarry,

I think you confused two separate cases by mistake... The BW1339 is a QUADRATRAC....TOTALLY different animal than the Selectrack.<HR></BLOCKQUOTE>

No confusion; I've got one of each.

<BLOCKQUOTE>quote:</font><HR> Speaking from the BW1339 knowledge that I have gained since ownership, is a FULL-TIME 4WD. there is no part-time... no shifter at all<HR></BLOCKQUOTE>

It is a full-time 4wd case, in the sense that it HAS a full-time 4wd mode (two of them, in fact, if you've got the low-range). It is also a part-time transfer case, as the 4wd mode with Emergency Drive engaged is a PART-TIME 4WD MODE, according to the Jeep definition. Emergency-Drive is the same type of 4wd mode present in the D20 and the NP208 in all ranges, the low-range in the NP228 and NP229, the 4wd-HI-Lock mode on the NP219, etc: Jeep considers it PART-TIME because it should only be used on loose-surfaces, and not under other circumstances (as they indicate a FULL-TIME 4wd mode can be used).

<BLOCKQUOTE>quote:</font><HR>(E-Drive is NOT a part-time operation... explained below), except those with a 2:56:1 low range reduction unit.
[snip]
I hope this sums up the confusion some....
<HR></BLOCKQUOTE>

E-drive IS a part-time mode. That does not mean it is a 2wd mode; I know that, and that is not my point. My point is that there are two different ways in which the adjective "part-time" is used, and that people often confuse the two terms. I also tried to show how Jeep's literature uses the adjectives "part-time" and "full-time" to refer primarily to the 4wd MODES its transfer cases use, and then, only secondarily, does it designate a transfer case as a "part-time", a "full-time" or a "full-time/part-time" transfer case, based on which 4wd modes a transfer actually has (more properly), or which are the primary 4wd modes a transfer case is known for (a looser use of the term).

Jeep's official use of the terms means the following, for the 4wd Modes:

Full-time=differentiated 4wd
Part-time=undifferentiated 4wd

My other point was that many people use the term differently from Jeep, and use the adjective primarily to refer to a transfer case as a whole, and generally use it to refer to whether it can be shifted out of 4wd (making it a part-time case), or whether it can't (making it a full-time case, since it's always in 4wd). So:

Part-Time=Can shift from 4wd to 2wd
Full-Time=Can't shift out of 4wd.

I'm not going to make charts and graphs and take 8"x10" glossy photos to make my case here. I'm just trying to make the point that there are different ways of using the terms "part-time" and "full-time", and that when you start speaking of the later NP229 and NV242 transfer-cases, Jeep's official terminology makes a lot more sense of the designation "part-time/full-time", which is a nonsense designation when you use the terms in that second sense of having a 2wd mode or not (i.e. it has a 2wd mode, so it's a part-time case, but then it's a full-time case because it's always got 4wd?). Rather, it's a "part-time/full-time" case because it has both modes.

And my point was, if the NV242 is a part-time/full-time case because it has both a locked 4wd mode and a differentiated 4wd mode, then a QT would, by the same reasoning, be a part-time/full-time case.

And YES, I know it doesn't have a 2wd mode, and you can't drive with front hubs unlocked, and it takes fluid that costs $10 a quart, and that the e-drive vacuum lines leak; I know, because I've got one. And a spare in the driveway. And I still say that e-drive is a PART-TIME MODE, not according to some crazy definition I dreamed up on my own after chugging a quart of vodka, but according to Jeep's normal usage of the term.

------------------
Bob Barry<UL TYPE=SQUARE>* '78 Cherokee 4-door
* '88 Grand Wagoneer[/list]http://studentweb.providence.edu/~rbarry/wheels/

[BobBarry]

<BLOCKQUOTE>quote:</font><HR>Originally posted by -joe:

Bob, sorry for snipping the above but this is getting way too hard for me to edit line by line.
From memory here...
You quoted the 88 Chrysler manual on PT and FT cases. For one thing by 88 when DC actually was in the Jeep business there were no PT cases in FSJs. The 208 was dropped in 87.<HR></BLOCKQUOTE>

The '88 manual looks like a reprint of the '87, and lists info for the J-trucks (of which only a handful of '88s were built), as well as for the I-6 and the NP208 case. So even if my truck was built after the Chrysler takeover (I think mine is an early version, built before the switch; still lots of AMC labels around on the thing), the terminology pre-dates it.

<BLOCKQUOTE>quote:</font><HR>I agree that the old time definition of PT meant that 4WD can only be used PT as on low traction sufaces. But FT's can be used on dry pavement in 4WD mode.<HR></BLOCKQUOTE>

My main point was that the above is Chrysler's meaning of the term, and Jeep's meaning, at least at the end of 1987.

<BLOCKQUOTE>quote:</font><HR>But the old terms also apply to PT having a 2WD mode which neither the 1339 or 219 have.
According to AMC from AMC factory shop manuals the BW1306/1339 QT is a FT case. The NP219 is a FT case. <HR></BLOCKQUOTE>

And that they are. As is the NP229. It's probably the case that at some point, Jeep started using the terms to refer to the modes, rather than the cases. It's just unfortunate, and the cause of some confusion, that they changed the way they used the terms at about the same time they also introduced a 2wd mode to the full-time cases. So they started calling the cases properly by the modes they used (so the NP229 was also designated as a part-time case because of its part-time 4wd mode in Low range), and some people thought that they were calling it a "part-time" case because it now had a 2wd mode. Heck, maybe the Jeep literature did use it in that sense.

But at least by 1987, Jeep had settled on using the terms to primarily refer to the modes a transfer case had.

<BLOCKQUOTE>quote:</font><HR>The 229 is a PT/FT case. Now if Chrysler wants to change the lingo(after the 219 and BW/QT don't even exist anymore) on
[snip]
I do agree with you that by todays/Chryslers and maybe others definition the BW/QT might be called a part/full-time case but AMC never did nor did Borg-Warner. Even the NP219 which was built by Chrysler(? NP?) is called a "full-time" case by their own definitions.
[snip]
I'll also get back to ya on the 192/162/161? F/L head, six cyl stuff from the 1FSJ list tomorrow via email. Need to pick your brain on this odd ball engine stuff.<HR></BLOCKQUOTE>

I posted a reply about those early-50's I-6 motors: the 148ci I-6 was a flathead only, while the 161ci I-6 came first in a flathead, and then in an F-head version, before being replaced by the Continental (a Kaiser subsidiary) 226ci flathead I-6.

But you're right; it is late. Now that my one-week old daughter is soundly asleep, I think I can hit the hay too; G'nite, John-boy... http://www.cs.colostate.edu/~zeimet/ubb/wink.gif

------------------
Bob Barry<UL TYPE=SQUARE>* '78 Cherokee 4-door
* '88 Grand Wagoneer[/list]http://studentweb.providence.edu/~rbarry/wheels/

[scotty]

my god-such a debate on full time/part time... i didnt think the end of this thread was ever going to come,either...

anyway,i only have a couple of comments:

first off,sorry joe,i somehow misread your comment to read something like "full time cases always have a 2wd",which didnt make a whole lot of sense to me,thus the references to the 119 and quadra trac.i honestly had no idea it would turn into a thread 50 screens long about the differences between part time,and full time.

2nd comment is about the 229 and bw 1339 "driving the rear axle until the front slips" .i dont think this an entirely accurate statement,and if im wrong id like to know how the xfer cases accomplish this feat. a diff is a diff,and a full time case has a differential,be it an open one with conventional spider gears(203,228) a limited slip with clutch packs(bw 1339) or a viscuous coupling(229). not to criticize,but this statement is like saying that a rear axle assembly drives the vehicle with the right wheel until the left one slips. in a full time case in full time mode,on a high traction front and rear wheels are pulling just like left/right are always pulling.

third,im glad you figured out what your xfer case is,puvong.

last and not least,new process/new venture cases by numbers,please. it causes confusion to call the 219 a quadra trac,even though this is what it was called,it is completely different than the bw 1339.

good night all...

------------------
scott
85 grand wagoneer
258/904/twin stick dana 300/dana 44/welded amc 20
38x15.5 gumbo mudders
snorkel/dual batteries/onboard air/"custom" convertable
3 inch body lift/mostly stock suspension/"modified" fender openings
custom front/rear bumpers and brushgaurd

[joe]

<BLOCKQUOTE>quote:</font><HR>Originally posted by scotty:
2nd comment is about the 229 and bw 1339 "driving the rear axle until the front slips" .i dont think this an entirely accurate statement,and if im wrong id like to know how the xfer cases accomplish this feat. <HR></BLOCKQUOTE>

Scotty, if I did say that waaaay back up there somewhere it's a typo. It most certainly should have read "till one of the *rear* tires slipped." Sorry bout that http://www.cs.colostate.edu/~zeimet/ubb/frown.gif
This the last you'll see of me on this subject. I'm a hunt-find-push typist and I've typed part-time, full-time, part/full-time so many times...I don't even know what I'm saying anymore http://www.cs.colostate.edu/~zeimet/ubb/smile.gif
Later,
-joe

[TPIGUY]

<BLOCKQUOTE>quote:</font><HR>Originally posted by -joe:
I'm a hunt-find-push typist and I've typed part-time, full-time, part/full-time so many times...I don't even know what I'm saying anymore http://www.cs.colostate.edu/~zeimet/ubb/smile.gif
Later,
-joe<HR></BLOCKQUOTE>

Joe, I can write you a keyboard macro for "part time/full time" if you want http://www.cs.colostate.edu/~zeimet/ubb/smile.gif

[River Beast]

Bobbarry,

AAAHHHHHH.... NOW I see your point. I guess I had to read what youwere saying agian to FULLY understand what you were trying to say. I agree with you... the E-drive is a "part-time" mode because you can't use it "all the time" (unless you have no front driveshaft http://www.cs.colostate.edu/~zeimet/ubb/wink.gif). Gotcha...I hear what your screamin'. Too bad some of us can't type as fast as we talk. I would be here for hours typing something that would have taken me 10 min to explain by voice (hehe)...

------------------
TJ
78 Wagoneer "River Beast"
360/TH400/QT
Dana 44's (soon to be 4.88's)
7" SOA conversion
4" Skyjacker Softride
3" Trailmaster Bodylift
33x12.50's on 15x10's
(soon 38.5x14.50's on 12's)
My FSJ site: http://www.geocities.com/~spazz4life (http://www.geocities.com/~spazz4life)
"Where there's a hill...there's a way!"

[BobBarry]

<BLOCKQUOTE>quote:</font><HR>Originally posted by River Beast:
AAAHHHHHH.... NOW I see your point. I guess I had to read what youwere saying agian to FULLY understand what you were trying to say. I agree with you... the E-drive is a "part-time" mode because you can't use it "all the time" (unless you have no front driveshaft http://www.cs.colostate.edu/~zeimet/ubb/wink.gif).<HR></BLOCKQUOTE>

OK, having convinced the jury, now let me make the case for the other side... http://www.cs.colostate.edu/~zeimet/ubb/wink.gif

I imagine Jeep never used the term "part-time" to refer to the modes on the BW1339 and NP219, to avoid confusion about what kind of transfer cases they were. Once they introduced the NP229, however, they probably figured there was less chance of confusion.

Also, terms are used for marketing purposes in ways that are not always technically accurate. So, while a transfer-case may be a full-time/part-time case, in technical terms, because it has both modes of 4wd available, the term may be used in advertising to convey the idea that the transfer case has a full-time 4wd capability, that can be switched on for part of the time, or that the transfer case has the capabilities of a full-time 4wd system, but the advantages of a 2wd that is usually found only on "part-time" transfer cases.

In actual point of fact, I just wanted to see this thread drag on to be 25+ messages and 100+ kilobytes in size (on my 14.4 modem, this thread takes forever to open! http://www.cs.colostate.edu/~zeimet/ubb/smile.gif

------------------
Bob Barry<UL TYPE=SQUARE>* '78 Cherokee 4-door
* '88 Grand Wagoneer[/list]http://studentweb.providence.edu/~rbarry/wheels/