So i was doing a bit of off-roading yesterday. My jeep is all-time 4WD, it’s either low or high. So I was in low for a bit and noticed a ‘clunking’ noise when i would make hard turns.
About 10 mins later, my front wheel drive was working intermitantly in conjunction with this clunking noise. A minute later, i had no front wheel drive, only rear wheel.
On the highway it drives fine no noise no noticable problems. But if i make a tight turn, at low speeds, i get this clunking noise again.
My guess is a blow diff, but i can’t figure out why i’m getting the clunking noise during a turn.
I have yet to crawl under and make a visual, i’m waiting for the mud to dry.
Usually when you hear noise turning it is the CV or universal in the front axle. I think jeeps have universals on the wheel ends, that would be the first place I would look. Had them go on my old Ranger before. Made a shit load of noise and could feel it in the steering wheel. The fact that it drove fine back in high yet still made noise turning makes me think its not a transfer case issue. The noise will be more pronounced at lower speeds and especially in low range because you’re sending maximum torque through the driveline at those low speeds.
No, that’s what’s a bit puzzling. Jeeps don’t have a front diff disconnect and especially yours with the full time 4wd. So the only way to lose power to the front wheels would be a break somewhere in the chain (front prop shaft, front diff itself, u joint, t-case, etc). All of these would cause pretty big problems and a very good chance you would have noticed something amiss on the road back in high. I’m guessing your t-case uses a viscous coupling for its AWD, they are pretty robust, but that could have went I suppose, but again you probably would also notice it all the time. Some of the noise could come from the planetary gearset used for low range. You could break something in here and have it act fine back in high (so long as no broken parts jammed up anything else). I would first start by checking the easy stuff, front wheel u-joints for play, front prop shaft for play, etc. Then work your way back to the t-case. Might not be a bad idea to pull the plugs on the front diff and t-case and see what the oil looks like. Could find an indication there to a problem.
The Laredo V8s with the fulltime 4wd do have New Process (241?) Tcases which are, in fact, a viscous coupling.
These VCs suck, at least in this application.
I had a 94 for a couple of years, after a few lite offroad trips and quite a few DD miles, I replaced the TC once (stocker gave up FWD after 120k miles), and then rebuilt the (reman’d) replacement TC ~20k miles later.
In the end, I guess I’m suggeting You finger the TC and check for shrapnel & oil condition.
Otherwise, You might have chewed the inned ends off of the front diff, but that’s a bit unlikely me thinks.
your transfer case is probly a np249 and i has the viscous coupler wich can go bad. when it does no power goes to the front wheels. your best bet is to switch to a 241 or better yet a 231 switching to either of those models will get rid of the VC and should be cheaper. good luck.
i know for a fact i have a viscous coupler. I replaced the transfer case about 8K miles ago with a rebuilt one.
It did infact sound like a crushing pop can. I’ve been driving it, and started getting a very slight ticking sound that corresponds with wheel speed (not engine speed)
i’ll crawl under it soon here is see if it’s anything obvious. Thanks for the input guys, i’ll keep you updated.
did a quick visual. U-joints appear to be okay, with no access play. I grabbed the front drive shaft and tried twisting it to see if it would spin freely. I did not move freely and i noticed it also trying to twist the rear drive shaft.
when i get a chance, i’ll check to see if the front drive shaft is being powered somehow.
The bad thing with VC’s is they’re very hard to test with little or no torque being applied, ie: spinning a prop shaft by hand, jacking all 4 wheels up, etc. They usually need a fair amount of a velocity delta in order to start to shear the fluid causing the coupling to start to lock.
took it to transit towne dodge… it was the mechanics first thought based on how it sounded. He did a run-through of everything else and confirmed the diff is shot…without having to pull the cover.
Yea I didnt think it would be the VC, when it goes you have full time 4wd at 100% so your tires would be chirping when turning hard at low speeds like you had “posi.” If i was you id enjoy the RWD while you have it, I hate my 249 tc, full time 4wd is teh suck. When mine goes ill be looking for a 242 Selec Trac from a I6 ZJ. I think my front diff is on its way out also, Its been whining since a little after i purchased the vehicle.