Quadratrac questions

[MonsterMash]

I don't know too much about Q-tracs even though I had a '76 Wag that had one. I was watching my friend's '75 Wag in the mud a few days ago and even with bald tires I never saw him spin a wheel! I know that Q-tracs had a sort of t/c differential that metered the power between the front and rear wheels but was there anything special about the differentials in the axles? Aren't they just open differentials similar to the ones in my '84 GW? Why didn't his wheels spin in the mud??????

------------------

'84GW360--"Spinner"
Bigger tires and better stereo but pretty much stock
Most everything works some of the time!

[Bahamut]

i would say i was just lucky

i honestly think my enginge is getting very tired

------------------
The Beast
1975 Jeep Wagoneer
Bald Tires
Old 360 4v
Leaking TH400
BWQT W/Reduction unit MUD MASTER
Delco Alternator(riged mounts)
Slightly Saggin Springs
Good Sound system
Parts Killer

[joe]

Trac-Loc's were never offered as options on QT equipped FSJ's but that's not to say in the rigs 25 year history someone hasn't installed LSD's into it.
-joe

[River Beast]

MM,

The BW1339 (QT) is a horse of a different color, for sure. QT's work just as an open differential would in a rear end.. to a degree. The center diff of the QT has brake cones that are spring loaded thru thrust washers to the center diff that are pre-loaded to break loose at a specific torque. Theoretically, when enuf torque is applied to either or rear and a wheel spins, all power should be transferred to that wheel that's spinning. That's why open diffs are not desireable for 4x4's. Now I said theoretically... remember?...good. I have had a similar experience where no spinnning is evident. I believe it's because of the brake cones and thrust washers allowing a certaining amount of torque to the axles BEFORE breaking loose into a spin. My .02 worth.

------------------
Todd
78 Wagoneer, "River Beast"
360/TH400/QT
Dana 44's locked w/ 4.89's
39.50x15x15 Super Swamper TSL's
7" SOA in front-7" Rear Shackle Inversion Mods
4" Skyjacker Softride
3" Trailmaster Bodylift
My FSJ site: http://www.geocities.com/~spazz4life (http://www.geocities.com/~spazz4life)
My E-mail: monster_fsj@hotmail.com
"If you can't stop...SMILE as you go under!"

'93 3/4 ton 4x4 Suburban...a.k.a. "FSJ Hauler"

[scotty]

what sort of mud are we talking about here? the kinda thick,sticky stuff,or real slick,slimy,been rainin for 3 weeks kinda mud? i would say that if you never saw any wheels break traction and spin freely,helplessly while the truck moved slowly,or not at all, then simply the available traction was pretty high,despite the fact that it was mud. if wheels dont spin,they have traction,and it doesnt neccessarily have anything to do with having an open diff or a locker or LSD. where a locker or LSD will help is when traction available is very different left to right and available power floats thru an open diff to the wheel with the least traction.

you can tell an open diff by jacking both wheels off the ground and spinning one.in an open diff the other side will spin the opposite of the one youre turning.a LSD or locker will spin the same direction. as joe said,in 25 years POs definately could have installed a traction device or 2(and done alot of goofy things).

yes,to answer the other question,the open diffs in the 75 perform exactly like the open diffs in the 84.nothing different or special-just spider and side gears inside a carrier.

yall shoulda been with me at haspin acres a few weeks ago.had done nothing but rain the whole time,and no one could go anywhere without much tire spinning. my girlfreind tried to follow down a big open stretch of mud to try and find a shelter to camp in,and i ended up having to pull her 2wd s10 back up to the front entrance when we found no shelters available. was very,very slippery.pretty much all we did that weekend was slide around. couldnt go anywhere real hairy since it was so slick,but still had loads o fun! he definatly would have spun tires there http://www.ifsja.org/ubb/smile.gif .



------------------
scott
85 grand wagoneer
258 with motorcraft 2bbl/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

T18/dana-spicer 18 with drum E brake and PTO swap very soon
searching for offset QT rear and PTO winch

[bignblue]

Joe, my '78 Chero w/tow package has a Trac-loc listed in the optional equipment list on the dealer's invoice--I still have all the original sales papers for this truck, which I *think* was originally sold to my old dentist! ("...it's a small world after all...") I wouldn't know what a LSD looked like if one bit me in the face, but I've had the diff cover off and there's definitely *something* there. JFYI...

[joe]

<BLOCKQUOTE>quote:</font><HR>Originally posted by bignblue:
Joe, my '78 Chero w/tow package has a Trac-loc listed in the optional equipment list on the dealer's invoice--I still have all the original sales papers for this truck, which I *think* was originally sold to my old dentist! ("...it's a small world after all...") I wouldn't know what a LSD looked like if one bit me in the face, but I've had the diff cover off and there's definitely *something* there. JFYI...<HR></BLOCKQUOTE>

Your is auto trans w/BW-QT right?
That's interesting because in the 78 factory TSM in the Drivetrain Combination Chart(pg A-12) there is a clear subnote(4) regarding the TracLoc that says "NA with QT". Also in the specific chapter titled Trac-Loc(pg 2F-43) the opening paragraph states it's "only avail with the D20 transfercase and not available with the Quadratrac".

Just curious but what is the axle code stamped into the boss next to the big dowel hole? If it's indeed a trac-loc diff it'd be N for 3.54's and M for 4.09's. Non trac-loc units will be either A or L. It should also have a tag between two cover bolts warning you the axle needs a special gear lube with a friction modifier in it.
-joe

[bignblue]

According to the tag, and previous inquiry the diffs are set up with 3.54 R&Ps. I've replaced the fluid and added the limited slip goo as per instructions. It's possible the Trac-loc was a dealer-installed option, but then again I could be wrong. I just looked at the invoice and now I don't see anything referring to an LSD!!! I may be confused here (never unlikely w/me), and I may be remembering what I was told instead of what I read. Dang it, I remember seeing a reference to Trac-Loc!!!!! I'll keep looking.

BTW, what's the "Extra Duty Suspension Package" refer to? Number of leafs in the pack? Also, there's a Spare Tire Lock mentioned but nowhere for the spare to mount! I mean, there's the empty space under the cargo area but a 31" tire won't fit in there as far as I can tell. Joe, I humbly apologize...it looks like I was wrong.


Next question, then: I had the rear of the Jeep jacked up yesterday to drop the driveshaft and to line things up I spun the right rear wheel. The left one didn't budge...what does that mean? I know the rear end is a little squirrely, and I have the gears and carrier to fix it but not the $.

[joe]

<BLOCKQUOTE>quote:</font><HR>BTW, what's the "Extra Duty Suspension Package" refer to? Number of leafs in the pack? Also, there's a Spare Tire Lock mentioned but nowhere for the spare to mount! I mean, there's the empty space under the cargo area but a 31" tire won't fit in there as far as I can tell. Next question, then: I had the rear of the Jeep jacked up yesterday to drop the driveshaft and to line things up I spun the right rear wheel. The left one didn't budge...what does that mean? I know the rear end is a little squirrely, and I have the gears and carrier to fix it but not the $.[/B]<HR></BLOCKQUOTE>

Bignblue,
I'm sure spring pack count is what they're refering to. There were a lot of various spring pack options over the years.
What the tire lock thing is, I'm "guessing" it's for the optional inside the cab spare mount but I suppose it could be for the underneath mount but it'd sure get dirty/froze up easy http://www.ifsja.org/ubb/frown.gif

I've never experienced your tire rotation situation. On anything I've ever had with both rear tires in the air and ya spin one by hand the tires spun opposite w/o a LSD and in the same direction w/ LSD. Never had just one spin and not the other? Hope someone can jump in here and explain this to both of us http://www.ifsja.org/ubb/smile.gif
My only guess is that you've got a brake shoe hanging up on the one that doesn't turn. An open diff(or one with a shot LSD) with only one wheel raised...it's turnable but not if it has a functioning LSD or locker.
-joe

[Ralphp]

Just for info., I looked through my original owner's manual from my '74 Cherokee and found that the Trac-Loc was offered only on "Conventional Manually Engaged 4-Wheel Drive Systems" and not on the Quadra-Trac.

[scotty]

bignblue, your wheel was stationary simply because the brakes on that side had enuff resistance to cause power to spin out the yoke,since the driveshaft was not connected. hook the driveshaft back up(or hold the yoke stationary some other way) and tell us which way the other wheel spins-same or opposite?



------------------
scott
85 grand wagoneer
258 with motorcraft 2bbl/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

T18/dana-spicer 18 with drum E brake and PTO swap very soon
searching for offset QT rear and PTO winch

[Michael F]

Scotty is right, but when you jack up the axle and turn one wheel and the driveshaft can NOT turn, the other wheel will turn in the opposite direction if you have a LSD or not, with the LSD it will be harder to turn the wheel because you will have to overcome it trying to keep the wheels together, with a spool or the side gears welded, the differential will no longer allow the axles to turn independetly and you will NOT be able to turn either wheel because the differential can not turn because of the driveshaft holding it.

When the driveshaft CAN turn and you spin a wheel one of two things will happen depending on what offers the least amount of resistance, the driveshaft will turn and the other wheel will turn the same way which may or may not mean you have a LSD (because the differential is turning) or the other wheel will turn the opposite way and the driveshaft will not turn (because the diferetial is not turning just the side gears) meaning you do not have a LSD or you have one and it is worn out.

------------------
81 Cherokee Laredo WT
53,000 orig. miles
360/727/208/3.31/31x10.5AT
79 Cherokee Chief WT (snow plow)
360/400/QTw/LR/31x10.5
My family has 7 FSJ's!!!

[scotty]

yeah,a misleading,not thot out,quick responce on my part. if you hold the yoke or driveshaft stationary,the other wheel will still spin opposite with a limited slip.



------------------
scott
85 grand wagoneer
258 with motorcraft 2bbl/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

T18/dana-spicer 18 with drum E brake and PTO swap very soon
searching for offset QT rear and PTO winch