Tranny sound?

Ok, here is something that has happened to the XJ all of a sudden. I’ve gotten some leads from Ghost and Eagle, but I figure it’s good to get some second opinions before I tear out the tranny….. er, make that Ghost tears out my tranny and I watch, dumbfounded

91 Cherokee, all stock, part time 4WD. About 200K on the drivetrain except the engine with was replaced about 20K miles ago. Auto tranny.

Backing down my driveway two days ago, it just starts to make a ticking sound. As Glenn put it, similar to a bike chain binding. As I drove to work, I noticed it slowly got worse. Got home and removed the front axle incase it was a bad u-joint. No help. Also put in 2 quarts of tranny fluid because it was getting low.

Sounds gets worse as the drivetrain heats up.

Sound is really clicky-grindy similar to a bike chain binding or a valve knocking with the valve cover removed, but under the Jeep.

Believe it times itself with the rpms, but cant remember as I sit here.

Sound happens more at take off through first and second gears. Very light while cruising, but if I give it a little more gas than it takes to just cruise, it comes back. Off the gas it’s almost non-existent.

If my drive shaft had a thick wire welded to it and it when the drive shaft spun the wire would smack the bottom of the truck, that’s about what it sounds like.

T-case chain????

I was wondering about that. One thing I havent had time to do yet is to check the tcase fluid. No shop dosent make it easy. I should probably drain it and check for debris.

SouthernXJ said:

I was wondering about that. One thing I havent had time to do yet is to check the tcase fluid. No shop dosent make it easy. I should probably drain it and check for debris.

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drop both driveshafts and get a stethoscope and have someone drive it while you lay underneath and listen. OR actually drop the driveshafts and listen and if still unsure get the stethoscope then.

drop both driveshafts and get a stethoscope and have someone drive it while you lay underneath and listen.

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Drop both shafts and drive it? Not following

SouthernXJ said:

Drop both shafts and drive it? Not following

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if you disconnect both driveshafts it will be sitting on the ground and you can "Drive it" without it moving on you and you can safely lay underneath and listen for the sound. Also you can place it on a vehicle lift (like in a shop) and raise it up

Are you sure its the tranny cause I have the same noise and its the exhaust hitting the front axle cause the hanger broke. I can feel it in the floor Right by my feet and in the passenger side.

I doubt it's exhaust. It's a very strange sound but next time I'm under it I'll push-n-pull the exhaust and see what happens.

"drive it" Ok, now I read ya. I was wondering how you got your creeper to roll that fast

mabey the flywheel bolts? just to throw something else at you. though i would think it would make noise all the time, not just in gear.

SouthernXJ said:

"drive it" Ok, now I read ya. I was wondering how you got your creeper to roll that fast

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I just tied myself to the vehicle and it pulled me . Anyways, I have found that to be a very effective way to diagnose a lot of problems/noises from underneath.

I have actually just noticed that same sound, so I know what you are talking about. I started hearing it after my driveshaft went out on a trip, causing tons of vibs. Since getting it rebuild, I've been hearing a ticking kind of sound from under the jeep. I thought it was the new shaft, but after crawling under today and listening it is either the T/C or the tranny. The sound seems to becoming from where the two meet together.

The fluid on my T/C is good, but I did notice that it gets EXTREMELY hot after driving for any time. It gets so hot that I can't touch it at all. It is so hot that it heats up the rear driveshaft from where they mate until about halfway down, so much that I really can't keep my hand on it.

Ideas?

Marcus

scoobyxj said:

mabey the flywheel bolts? just to throw something else at you. though i would think it would make noise all the time, not just in gear.

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That is what I was thinking too could be a possibility. And may not make noise while out of gear. I had an old dodge that I put a high stall convertor in and the bolt heads were thicker than the stock ones. When you put it under load, as in "in gear", it would make a nasty sound as the bolts hit the inspection cover. Out of gear it made no abnormal sound.

I found an easy way to reproduce the sound that mine is having. If I have it running and put the transfer case in N with the tranny in D I get the noise. With the transfer in gear and the tranny in N I don't hear a thing. This is on an automatic. Ideas? I still have a warranty and the local dealer is cool about working on modified jeeps so maybe I will let them take a look.


Marcus

I just solved a similar grinding noise and it ended up being my rear ujoint on the back driveshaft. The thing was so destroyed that I was eating into the yoke, thus the grinding sound. I am glad that it wasn't something more serious (I am knocking on wood here) Let us know if you solve the problem!

Yeah, may as well put new ujoints in the rear, probably have time Wed to get under the Jeep.....