NP208 Whine? (87 J20)

[Narnian]

Until yesterdays snowfall, I had never had the J20 I bought in November past 15 mph in 4WD. I put it in 4H yesterday to drive home. At 20 MPH the transfer case starts whining just as if it were in 4L. I was afraid to go past 45MPH. Is this normal?

I pulled into a parking lot and pulled it into 4L just to make sure I hadn't missed the 4H. 4L engages and it did feel like it was driving in a lower gear. The 4Lock light never comes on. (when is it supposed to come on?) The 4WD light comes on in both 4H and 4L.

Is it possible that I am low on transfer case fluid? Or is this normal? My Quadratrack is generally quiet in 4H.

[ December 05, 2002, 10:17 AM: Message edited by: Narnian ]

[joe]

Originally posted by Narnian:
Is it possible that I am low on transfer case fluid? .That's very possible...likely too. When was the last time you changed the fluid in it? I don't know about your 4WD light...some 80's rigs didn't have them.

[Narnian]

GFD said he changed the fluid a few months before I bought it. I guess I can pop by the jiffy lube and have them check.

[Narnian]

Hhhmmm... (Reading through the owners manual)

Was I hearing whine becuase there wasn't enough snow on the road and the gears were binding?

In the Cherry with QTrack I could put it in 4HLock and I didn't have trouble hitting pavement occasionally. Is the 208 more demanding of loose surfaces? I think I even have the trac-lok on the rear axle which would allow less slip.

[joe]

Yeah, that would do it. The 208 is a part-time x-case and you can't drive a PT x-case on dry, non-slick roads or yes the drivetrain will bind up and something will break.
Quadratrac's either the early BW units or the later NP's are both full-time x-cases with clutch packs or viscous couplers to allow for slippage in 4WD on dry roads, the part-time x-cases have no such provision and require a tire to slip occasionally to relieve the binding.

[Narnian]

OK, So basically, with the NP208 (unlike my NP219) I need to keep it in 2WD unless I am on packed snow. A slightly slick road is not slick enough for 4WD. Right?

[joe]

Humm...you said you could drive your QT rig in LOCK on dry roads? Either you were pretty lucky or it wasn't really locked in. The pattern on an NP219(psuedo-QT) is 4L-N-4H-LOCK. In 4H it's not locked, only in 4L and LOCK is the coupler locked solid and can't slip and then acts just a conventional part-time case in 4WD.

[joe]

Originally posted by Narnian:
OK, So basically, with the NP208 (unlike my NP219) I need to keep it in 2WD unless I am on packed snow. A slightly slick road is not slick enough for 4WD. Right?Slight slick snow etc is fine but if you get stretches of dry pavement(rain wet doesn't count) in between just shift back to 2WD. When it gets slick again shift back to 4WD. You can do this at reasonable speeds. You're not going to be wanting to do 50 mph on ice anyway so by the time you slow down to safe speed just click it into 4WD. When I run the hwy in winter with a PT x-case I'm always shifting between 2WD/4WD at 35 mph or so as road conditions warrant...no problem.

[Narnian]

Oh! I didn't know you could shift when traveling that fast. I've been slowing down to 3MPH, putting the transmission into nuetral, then shifting.

As far as the NP219 goes, I really don't remember what I did last winter. I was probably using 4Lock only when I was driving on solid snow, and using the 4H the rest of the time.

I miss my Cherry! I need to get that tranny fixed.

[Ralph]

Where's that whining sound coming from?

Oh, it's Narnian... smile.gif

The NP208 does make a bit of noise when you have it in 4wd on dry pavement. That's what's in my J10. Just make sure you have it filled with fluid -- it uses ATF.

As for shifting, you should be either at a complete stop or going just coupla-three miles per hour when engaging shifting that transfer case. It's not like a NP229 that you can shift on the fly at 60 mph (in which case the viscous coupler takes up slack while the shift is taking place).

[ December 05, 2002, 06:27 PM: Message edited by: Ralph ]

[Jeep Craze]

If your front axle has manual hubs, and they are LOCKED you can shift from 2wd to 4Hi at any speed(suttable for the conditions) Make sure your tires aren't spinning(the back tires can't be slipping) like when you pull out and the tires are spinning DO NOT yank the lever. as long as the front hubs are locked then your front tires are spinning the same speed as your rear. Therfore if you switch 2hi-4hi you will not encounter any complications. I leave my front hubs locked all winter(80 j10 360/176/208)and just yank the handle when needed even driving at normal speeds.

Craig

[joe]

Originally posted by Ralph:

As for shifting, you should be either at a complete stop or going just coupla-three miles per hour when engaging shifting that transfer case. Really? I just recently got my Chero(w/208) and haven't tried to shift it into 4H at say 30 or so but that would be the first part-time x-case I've ever owned where you couldn't shift on the fly including various D18/D20/D300's and a couple of Toyo LC x-cases.
Hummm...the TSM says nothing about having to come to a stop or slow roll either? Oh well, if we get some snow this year it'll be the first thing I try. I'll let ya know what happens. smile.gif

[Narnian]

Well! There seems to be some disagreements here.

I guess I'll study that owners manual some more and see if it says anything. I know that with my NP219 if you want to go from 4H to 4H Lock the manual says to slow down to < 5 mph, put it in nuetral, shift, put it back in gear and go your merry way. But now that we are discussing it, I don't remember seeing those instructions in the J20 manual for the NP208.

And yes Ralph, the biggest whine is coming from me. I'll add some cheese and we'll be set!

[mtn goat]

my chero has the 208 and I can go from 2H to 4H all day long at speed...as long as the hubs are in. now to get to 4l, you have to be stopped...or going very slow.

[Ralph]

mtn goat, you're obviously braver than I when it comes to shifting into 4Hi at speed. Here's what my 1984 Owner's Manual states at pages 19-20:

Shifting Procedure

1. With vehicle stopped, set hubs to desired position.

2. Start vehicle moving 2-3 mph (3-4 km/h) or if already moving with hubs in desired position, reduce vehicle speed to 2-3 mph (3-4 km/h).

3. Shift automatic transmission to N (Neutral).

4. Shift transfer case to desired position.

5. Shift automatic transmission to desired position.

4-Wheel Drive Cautions

* Never operate in 4-wheel drive on dry, hard-surfaced roads for a sustained period, and use 4LO only when needed for added pulling power. Using 4WD on such rodad will cause stress and possible damage to components, as well as make shifting difficult. To reduce shifting effort, drive the vehicle in reverse for a few feet, or drive off the hard surface road momentarily to allow tire slippage.

* Never attempt to engage LO range when vehicle is in 2WD, or when vehicle is moving faster than 2-3 mph (3-5 km/h). Transfer case damage may result.

Okay, now you guys do it your way! smile.gif

[crispyboy]

I have an 86 j-20. It has always had some whine to it. I have had it taken apart when I had transmission troubles and they replaced a bearing at that time but the noise has never changed. It has a slight whine in 4H but 4L is really whiny but I love the sound. Nevertheless I have shifted in and out of 4H on snowpack at highway speeds when my hubs are locked in but I make it a point to not drive my truck in the winter as we usually have salt on the roads. Truck shifts easily into 4L when stopped but I need to have a slight role when going back out of 4L. Also there is only one dashboard light that tells you when 4wd is engaged.

[Narnian]

Thanks on the light info 13lftmfsj. I'm thinking that "lock" light is only for the full time transfer cases.

I went through the manual for the 87 J20, and it says exactly what Ralph's manual says, except that mine adds a paragraph about shifting tecniques.

It kinda maskes sense that it should work at higher speeds if you are traveling in a straight line, since the front should be turning at the same speed as the rear. However, if you are turning at speed I think you would risk totally trashing the gears. The outer wheel would be turning a lot faster than the inner wheel and the front wheels would be turning faster than the rear wheels. With manual hubs there is no synchronization built into the system.

If there are a bunch of you who have done it for years successfully I'd like to hear about it. Perhaps Ralph and I are following instructions that are meant to prevent the worst case scenario, and we really don't need to be so conservative.

[Narnian]

Originally posted by 13lftmfsj:
Truck shifts easily into 4L when stopped but I need to have a slight role when going back out of 4L. I have not been able to shift into 4L without a slow roll forward in Nuetral. Anything else and I hear horrible grinding noises. I even tried shifting with the truck in park and the engine off. When I started it back up I heard grinding.

[Jeep Craze]

Hey Narnian,
You said that you can see that if the front wheels are turned(like going around a corner)that it would cause issues when engagine at speed. That is what I stated in my last message to you. As long as you are going straight w/ ur front hubs locked and your rear tires not slipping you can shift from 2hi to 4hi at any speed. Think about this. If your front hubs are locked that means that as fast as ur tires are spinning so is the front driveshaf. Therfore, When you pull the lever from 2-4hi all you are doing is connecting the front driveshaft w/ the rear. There should be no grinding or binding whatsoever. If you do encounter grinding I woudl say there is something wrong w/ your front diff/hubs.

Now if you are shifting from 4hi to 4lo you shoudl be moving 3 mph to encounter a smooth transfer. When you are sitting still and going past the N position on the transfercase it is sometimes difficult to engage again if you aren't moving or if you still have it in gear. Automatic.....put it in nuetral and going 3mph shift it to 4lo. and vise-versa when going back. In a manual trans, I put it in gear, w/ the clutch engaged and while rolling just enough to say I am moving I make the switch past n to 4lo and back again. I am sure there are alot of other people that shift on the fly w/ the 208. Craig

[kyjman]

Would it make any difference in the shifting technique between an auto/manual ? I have shifted my 208 while on the move and no problems, but I run the T-5 manual.

[Ralph]

The same manual I have gives separate but similar instructions for a manual tranny (T-176):

Shifting Procedure

1. With vehicle stopped, set hubs to desired operational mode.

2. Start vehicle moving 2-3 mph (3-4 km/h) or if already moving with hubs in desired position, reduce vehicle speed to 2-3 mph (3-4 km/h).

3. Shift transmission to N (neutral).

4. Shift transfer case to desired position.

[Narnian]

Well I didn't try it at highway speed, but I did try it at fifteen mph, without going to nuetral. It shifted with less effort than when I slow down, and there were no grinding noises or exploding bolts.

(Actually, I wasn't paying attention to what I was doing and shifted as if I was in the old Jimmy. If I had thought about it I would have slowed down and slapped it in nuetral first)

So I guess it's probably safe to do, if you do it as we described - straight line of travel and not gunning the gas. However - "just in case" the engineers had a good reason that we don't know fo writing the manual the way they did, I'll stick to shifting the way the manual tells it. I'll take a chance with it now and then if I'm getting on an off snow, which I never would have considered previously, but in general I'll go by the book.

[ December 08, 2002, 12:35 AM: Message edited by: Narnian ]

[will e]

You assume the engineer wrote the manual!!! smile.gif

I do as the manual says. It whines a little in 4wd HI and a lot in 4WD Lo. I don't encounter snow here in AZ so I only do this while wheeling. Basically, I put it in 4WD when we start and take it out when we finish. Depending on the terrain I go from Hi to Lo. I might try it at a higher speed next time. At the end of the Day. With the road in sight and a buddy who has a tow strap!

I think I saw a link in the tech section on how to do it STOPPED. I will go see if its there.

Oh. I have an 81. There is one light on the dash. It is orange. It comes on when I am in either 4wd Hi or Low. Kinda freaks me out when I am wheeling beacause I can see the dash light in my periphial vision.

[will e]

Found them.

Check out this ISFJS link:

http://www.ifsja.org/tech/tcase/tcaseinfo.shtml

And this one too:

http://www.ifsja.org/tech/tcase/hitolo.shtml