U-Joints

Ok guys, I just went through the suspension on my XJ again to try and find the damn clunking in the center of the floor....found nothing. Everything is tight, bushings/bolts...all tight. It’s going in for an alignment check on Tuesday, I’m having the guys at my local “Jeep” place give me their .02 on the source of the clunking.

One thing I did find was the front passenger axle u-joint had a tiny bit of play. When I say tiny, I mean you have to be right up to it to see it. That said, I’m going to do at least both axle u-joints.

I have searched and found many threads and posts regarding u-joints on the XJ. Trouble is, many contradict each other. I’d like to get a clear answer on wether or not ALL the u-joints are the same. I am running an OEM front DS as a rear with my hack-n-tap SYE. So I am wondering if the u-joints in the axles, and the u-joints in the drive shafts are all the same. If so, I might just buy 8 u joints and replace them all now!

I have to imagine someone out there knows if the XJ uses all the same u-joints in all locations.

Thanks for any input!


Sent from my iPhone using Tapatalk

I can say with 100% certainty that the same PN will not work in all locations if only for the fact that the retaining clips are different. On the axle shafts, it's a C clip that goes around the circumference of the cap, inside the ears on the shafts. On the driveshafts, a "E" clip is used that the fits inside the circumference of the ears on shafts, on the outside of the caps. Besides that, per Rock Auto, the caps are different sizes (1.063" vs 1.188" diameter). I wouldn't let that stop you from replacing them all thought...

check the tranny mount, may be worn out

Thanks for the input guys!

The only reason I wouldn’t do all the u-joints now is if they are not all the same. If the axle joints are different then I’ll just get a set and do those. The driveshaft joints are in decent shape.

All mounts are brand new (transmission and both motor mounts). Just to check, I out the XJ up on the lift today and grabbed the tranny and tried moving it up/down/around....nice and snug in its place...ugh


Sent from my iPhone using Tapatalk

Check motor mounts, check trans mount, check exhaust mounts. Check transfer case shift mechanism bushings. Inspect exhaust for signs of contact with cross member or unibody.

Did you install good quality mounts, or the crappy lowest price ones from IdiotZone or Advance ?

Driveshaft u-joints are a different Part number than axle shaft u-joints. Unless totally FUBAR u-joints are not a typical source of clunking.

Did you grease the rear driveshaft slip yoke !

BigNuge said:

So I am wondering if the u-joints in the axles, and the u-joints in the drive shafts are all the same. If so, I might just buy 8 u joints and replace them all now!

Click to expand...

No, the axle and driveshaft joints are different

Denny's is my preferred source for Spicer which is the reference link

Front axle joints are 5-760x (non-greasable, Spicer does not have a greasable but others do)

Driveshaft joints are 1310 series, either the 5-1310X non-greasable or the 5-153X shoulder zerk or 5-1310-1X cap zerk. When you rebuild the driveshafts you should buy the matching center ball too.

Non-greasable joints have tight seals to retain the lubricant. Greasable joints have a looser seal that allows the new grease to push the old grease out. But looser seals mean they will pickup more water too, so if you go with greasable you MUST grease them regularly to keep them fresh. They will last longer in the long run but cost of ownership is higher.

Thanks for all the input guys, I’ll try and answer all below.

jeep ride said:

Did you grease the rear driveshaft slip yoke !

Click to expand...

Yes, both of them! Every grease fitting under the Jeep has got attention.

Tim_MN said:

Check motor mounts, check trans mount, check exhaust mounts. Check transfer case shift mechanism bushings. Inspect exhaust for signs of contact with cross member or unibody.



Did you install good quality mounts, or the crappy lowest price ones from IdiotZone or Advance ?



Driveshaft u-joints are a different Part number than axle shaft u-joints. Unless totally FUBAR u-joints are not a typical source of clunking.

Click to expand...

Motor and transmission mounts are brand new. Yes, they are the cheepy mounts (bought online). I have put the XJ up on my lift, reefed on the transmission, trans is nice and snug. Used my 48” pry bar, motor mounts look great. All 3 mounts look like the day I installed them (only ~400 miles on them). Xfer case shift mechanism has been completely removed and replaced with an Azzy linkage setup (xfer case shifts awesome in and out of all modes). I did end up tweaking the exhaust hanger arm at the crossmember, looked like it might have touch the crossmember at some point (was only clearing by 1/2”). I was able to open up that clearance to 1 1/4”. Unfortunately I still have the clunk after tweaking that hanger.

ehall said:

No, the axle and driveshaft joints are different



Denny's is my preferred source for Spicer which is the reference link



Front axle joints are 5-760x (non-greasable, Spicer does not have a greasable but others do)



Driveshaft joints are 1310 series, either the 5-1310X non-greasable or the 5-153X shoulder zerk or 5-1310-1X cap zerk. When you rebuild the driveshafts you should buy the matching center ball too.



Non-greasable joints have tight seals to retain the lubricant. Greasable joints have a looser seal that allows the new grease to push the old grease out. But looser seals mean they will pickup more water too, so if you go with greasable you MUST grease them regularly to keep them fresh. They will last longer in the long run but cost of ownership is higher.

Click to expand...

I have ordered a set of spicer joints for the front axle, to be installed next week.

I do plan on going through the drive shafts soon.



Sent from my iPhone using Tapatalk

When you say clunks, can you be more specific?
Are they:
normal driving in 2 wheel
normal driving in 4 wheel only
starting out from a stop
stopping
only when shifting gears
only when braking
only when going over bumps
on and on

xjnp242 said:

When you say clunks, can you be more specific?
Are they:
normal driving in 2 wheel
normal driving in 4 wheel only
starting out from a stop
stopping
only when shifting gears
only when braking
only when going over bumps
on and on

Click to expand...

Normal Driving in 2 wheel (and 4 wheel): yes (when going over bumps)
Starting from a stop: no
Stopping: no
Shifting gears: yes (sometimes, not every time)
Braking: no
Going over bumps: yes, moderate or bigger bumps

Every u-joint in the Jeep is tight, with exception to the microscopic amount of play in the passenger/front axle joint.

I have been under it pulling/pushing/twisting/banging on anything that might cause this noise. Did all of this while it’s up on the lift, did all of this with it sitting on the ground....I am at a loss...


Sent from my iPhone using Tapatalk