transfer case problems...

ok, just got my first jeep a little over a year ago. stock 95 xj sport, aw4, 231. i had a mechanic check it out before i bought it, and he said the 4 wheel ran fine. given the different sized front/rear tires it had on it, i didn't want to use it. recently i got a set of bfg at's, and decided to try out the 4 wheel in a gravel lot. no dice. all it did was buzz when put in 4h. no significant power at all. the odd thing about it was that when the trans was put in neutral to take it out of 4h the buzzing continued until the t-case disengaged. i figured something inside was shot, and i would just take a look when i had money/time to get it fixed.

well last night we got a pretty good bit of snow, and trying to get out of the parking lot that is my driveway was a no-go in 2wd. i figured what the heck, might as well give it a shot again. put the trans in neutral, t-case in 4h, then trans in drive, and it went! much to my surprise, i got out of my driveway just fine. trans back in neutral, t-case back in 2h, and trans back in drive, and it ran just like normal.

just before work, i came to a spot that was heavily covered in snow, so i decided to give it another shot. stopped at a sign, trans in neutral, t-case in 4h trans in drive, and gas. all was fine for about the first 50-60 feet. enough to get up and over the hill, then power cut and the buzzing started, engine still running, and i started to coast. quickly shifted the trans into neutral, and the buzzing continued. stopped, put the jeep in park, released the brakes and it continued to roll. then i wasn't able to get the trans out of park. turned it off, worked the t-case lever back and forth a few times, restarted, and came out of park. made it to work in 2h.

any ideas? i'm starting to think maybe shift linkage? previously i'd thought chain in the t-case, but given that 4h definitely worked earlier, i really doubt that now. would love any help i can get here. thanks guys.

1. Parking brake is unrelated to the transmission/transfer case--try adjusting your rear brakes, and then if necessary adjust the parking brake cable.

2. When shifting in and out of 4Hi you can do that at ANY LEGAL SPEED, with no need to shift the transmission into neutral. You should be moving at a minimum of 2-3 MPH.

3. When shifting into 4Lo put the transmission in neutral, then shift the transfer case to 4Lo while moving at approximately 2-3 MPH.

Sounds like you were not getting the transfer case fully engaged.

You may need to adjust the transfer case shift linkage. Remove the transfer case shift bezel from the console. Move the transfer case lever all the way back to 4Lo. Put a 3 mm (1/8") shim between the rear shiftgate and the lever--a drill bit works great. Lock the shift lever against the shim and rear gate using a bungee cord around the lever and hook it to the seat frame. Now, crawl under the XJ. On the top shift rod is a square hunk of metal with a bolt sticking out of it. That square piece of metal is the trunnion, and the bolt locks it in place on the rod. Loosen the bolt but don't remove it. Now, follow the lower rod to the transfer case shift tab. Using a pry bar or large pair of pliers make sure the transfer case is fully shifted into 4Lo. Now, tighten up the locking bolt in the trunnion, remove the bungee cord and shim, replace the shift bezel. Have a cold beverage, you are done.

thanks so much for the run-down. as soon as things thaw out around here, or i can find a garage to borrow, i'll have a look at that. very nice to know since shift linkage adj. is almost free as opposed to the potential several hundred for most anything else that could have been wrong.

vintagetech said:

thanks so much for the run-down. as soon as things thaw out around here, or i can find a garage to borrow, i'll have a look at that. very nice to know since shift linkage adj. is almost free as opposed to the potential several hundred for most anything else that could have been wrong.

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You should try and get under there and hose down the trunnion, locking bolt, and that upper rod each day for a week with PB Blaster--I just noticed where you are located!

Last year one guy had to pull everything out and beat on it to break the trunnion loose it had rusted so bad.

so i've pretty conclusively determined it is in fact a linkage problem. took it out in the parking lot last night, and with 10" of snow i wasn't too afraid to play with it some. i found that if i shift it right, it goes in and out of 4 wheel very reliably. it'll need some small adjustments, but it's not too bad, and with a gentle hand it's fully functional as it is.

that said, i do still have a few questions about the t-case being new to 4x4 vehicles. 1) that buzzing/vibrating, i assume, is bad for the t-case? it certainly sounded bad, and i'm not exactly sure whether it was almost in 4hi from 2hi, or almost in N from 4hi. 2) joe mentioned that i could shift at any legal speed into 4hi. it it bad for the case to do this from stopped? i can certainly see how it could apply a shock to the chain if the rear wheels are slipping and the front are engaged. 3) now knowing that i don't need to use neutral to engage 4hi, is it a problem to go in and out of 4 wheel frequently? as you mentioned, pa roads are pretty crappy in the winter, and one of the biggest problems is that they get partially cleared when plowed. you'll frequently find several hundred feet of fully snow covered and slick pavement on an otherwise clear road, and sometimes those stretches come up unexpectedly. my main reason for wanting the 242 would be the full time position, to prevent lots of in/out of 4hi.

one final observation: 4 wheel drive is a lot of fun. my snow covered parking lot is now well decorated with tire tracks.

thanks guys.

Shouldn't be any issues going 2wd to 4hi.

Since this is your first 4x, remember, it does not help you stop any faster...just helps you start going and keep going....

Don't engage the 4wd when you are spinning your rear tires. This will stretch the chain in the transfercase. just let off the throttle and firmly pull the shifter into 4wd.

It may just need to be worked a few times to loosen the linkage up.

ahh... should have re-read joe's original answer, thanks.

just to clarify, into 4hi:
while moving, best bet
while stopped, not so bad
with tires spinning, bad plan

vintagetech said:

ahh... should have re-read joe's original answer, thanks.

just to clarify, into 4hi:
while moving, best bet
while stopped, not so bad
with tires spinning, bad plan

Click to expand...

Yeah, don't be spinning the rear wheels.

A little movement, hence the 2-3 MPH minimum applies to 4Hi and its min/max for 4 Lo, helps things line up and engage.

Have you checked the t-case fluid? Needs ATF, Mobil-1 Dextron III is a good choice. Might want to drain and refill with a good synthetic. ALWAYS remove the fill plug first. Sometimes they are a little seized and you don't want to drain the t-case with no way to refill it.