Topic: Clicking / Thumping. Transfer Case, U Joints, Hub?

[DanMarino]

Just drove the jeep and it only makes the noise when it is rolling.

Is there anything up front besides the wheel hub that could be bad?

[Jeffy]

Hi Jeffy and guys.

OK here's the best way I can describe it.   Unfortunately, I am deaf in one ear so locating where noises are coming from is impossible for me.

The transfer case is in 2 H.  The yoke on the front differential can spin freely in either direction.  If I rotate the yoke back and forth changing direction there seems to be some play or slop in the gears.  When the direction changes when I spin it left and right, there is a clunking when the direction changes.

The yoke on the transfer case spins freely in either direction.  If I rotate is back and forth changing direction it also seems to have some play in the gears and there is a clunk when the direction changes.

So is that normal, or an indication of something wrong?

Thanks,

Tom

If you're in 2WD then the front yoke on the transfer case will not turn with the driveshaft off.  Have you tried jacking the front end off the ground and giving the tires a good shake?  There should be no play when you pull and push the tire.  To clarify, you're not rotating the tire your seeing if there is any lateral play.  You should be facing the tire and pushing and pulling at the sidewall of the tire.  Also try spinning the tire my hand.  Can you feel anything?

[DanMarino]

Thanks again Jeffy for answering to my questions.

The very first thing I did to troubleshoot was:

I jacked the car up and looked around.  I pulled and pushed on both front wheels and didn't get any movement. Lug nuts were tight. Wheel bearings/hubs seemed tight. No play observed in tie rods or steering stuff.

I spun the wheel and it sounded fine.  I pushed and pulled at the 3PM and 9PM portions of the wheel to check for play.  I pushed and pulled at the 12PM and 6PM portions of the wheel and checked.  All seemed tight.  Nothing seemed loose.

If a front Axle Shaft U joint was bad, I would have experienced play doing that test, right?

I guess I'll go ahead and get some new u joints for the front drive shaft since they are original to the car and the drive shaft is out.

I definitely notice the clunking noise most when I turn right at an intersection, or turn right onto my street.  If I'm coasting and it is clunking it seems to get louder when I turn right.  Not so loud when I turn left or am coasting straight ahead.

I'll look at the rear U joints again and pull that axle as a process of elimination, but the rear u joints all seem fine and tight when I shake, push, and pull on the rear drive shaft.

[DanMarino]

From doing more reading, is it possible that the clicking could be coming from the front axle shift fork mechanism?

[Jeffy]

When you push and pull on the wheels you're checking the wheel bearings mostly.  I think you shoud have a passenger ride along and have them listen to see if it's coming from the front or rear.  Though if it's coming from the rear you'd probably hear it through the floor as well.  Checking the shift fork is easy though.  4 bolts and the cover comes off.

[Jeffy]

I should mention you can pull the outer shaft without having to disassemble the whole spindle by taking the discs off then unbolting the wheel bearing from the knuckle.  There are only 3 bolts and the while assembly will come out as on.

[DanMarino]

I drove it today and it is getting to make more noise.  As I pulled into the driveway on my way home from work the clunking was there, plus some louder popping noises.  I'm about to head to the garage and take a peek.

Also, any idea what part number I should buy to replace the drive shaft u joints?  Should I go with Spicer u joints?  Looked like there are different part numbers for ABS vs. non-ABS vehicles for some reason.  I have a 1994, non ABS, 4 banger, AX5 tranny.

[DanMarino]

OK tonight I found a definite problem.  I jerked around on the rear driveshaft and it was solid.  Same with rear shocks, rear track bar, front track bar, and front shocks.
Jacked the driver side front wheel up and removed the front driver tire.
Found that my driving today made the driver front axle shaft u-joint even looser.  Visible play and slop at the u-joint.

Thanks so much for everyone's help.

Now, how tough a job is it to replace the axle shaft u-joint?  I'm about to watch a youtube tutorial.  :)

[Jeffy]

Like I said, unbolt the caliper and take the disc off.  Then undo the three bolts on the backside of the knuckle that hold the wheel bearing on.  I think they're 15mm.  Once those are off the whole spindle will come out.  Then you can work on it on a bench.  A U-joint press or a large vice is helpful.  Though I've used the two socket method as well.

I'd go ahead and do both sides for piece of mind.  Those are non-serviceable U-joints on there and they're the same age so unless you want to do it again, probably soon, change them both out.  Also, what year is your Jeep.  Depending on the year they're either 5-260x or 5-297x.  If they're 5-297 then you'll want to get 5-760x since Spicer has discontinued the 297.  The 760 is around 20% stronger as well.  If you have a pre-94 then you probably have 260's and there's no upgrade.

[sharpxmen]

edit: deleted my post as it is irrelevant - you already found the problem and i was answering something 10 posts back. Glad you got to the bottom of it.

[DanMarino]

I have a 1994 YJ so the correct u joint is 5-760x?

[Jeffy]

I have a 1994 YJ so the correct u joint is 5-760x?

I think they're 297's but measure the caps first.  (260x) 1.06" OD Cap dia. vs (297x) 1.18" OD Cap dia.

[DanMarino]

Thanks for all the help, rolling great now with both front axle shaft u joints replaced.