Just Jeeps of Omaha

I've replace the front u-joints last weekend that were in horrible shape. I thought it was where this clattering noise was coming from every time I stepped on the gas. Although the u-joints fixed my death-wobble, the clatter is still there.

It sounds like it's coming from directly under the driver's seat or further back. Here's what I've noticed:

1) The noise only happens when I step on the gas in a forward gear
2) It is a steady loud clicking noise that gets faster with speed
3) Shifting gears does not slow or speed up the clatter (I was thinking that that might point to a tranny problem)
4) 2wd vs 4wd does not matter
5) Rolling downhill in neutral there is no noise

If anyone has experienced this please let me know. I'm going to head over and help FOZ on Saturday and possibly Sunday (if the warden lets me out of the house). If anyone stops by that knows something about this I'd love to hear your input.

Thanks!
Chris

Have you checked the drive shaft u-joints?

When on the gas, there would load on the rear drive shaft u-joints. In neutral, no load.
It would be easy to check.
Block the wheels, and put the transfer case or transmission in neutral, and check for play.

The other item to check would be the transfer case.
Check for play between the front and rear outputs. Also check for play when transmission is in gear.

I've checked the front and rear drive-shaft u-joints and can find no play. I have not checked it with the transfer case and tranny in neutral... I'll try to do that tonight when I get home from work.

On the transfter case when you say "check between the front and rear outputs", do you mean for play at the point where the yolk goes in? Or is there something else I should be checking?

I was tempted to disconnect my rear driveshaft and drive it in 4wd to see if the clatter still happens... If it's the transfer case I should still hear the noise and if it's the driveshaft or rear end I should not... Correct?

Unless it is in neutral, you won't be able to tell because there will be load on the rear ds. I forgot to mention that you should jack up one wheel so that the rear ds will spin.


If you put the transfer case in 4 wheel drive, transmission in neutral, jack up one front and one rear tire (or disconnect drive shafts). Try spinning the front/rear output (yes, where he driveshaft connects up) and see if there is play between the two, or if they both spin without any slop.



If it is not the rear driveshaft, you will be able to tell, but you will loose fluid from the transfer case because of the slip yoke (unless you have a slip yoke eliminator installed).

i have the same sounds as well... started after i got my 8.8 in... get a fast clatter above 35-40, clatter only comes around when im barely on the gas or not at all... with the clutch in to down shift, noise is still there... checked all the above. Any other ideas?

My clatter is when I'm on the gas and not off... and it even happens at slow speeds (15 - 20MPH) and then gets faster with the speed of the Jeep.

I haven't had time to try the fixes that MudNRox posted for me... maybe this weekend... I'll post back with my findings and would appreciate it if you did the same.

Thanks!

It may also be gear related.
You can pull the diff covers and inspect the differentials and replace the fluid if no problems.

Gears that are setup incorrectly can make noises when on or off the gas.

derek just put 4.88s in my jeep with a ford 8.8, clatter didnt start until after it left his shop... ill check the gears when i get back to nebraska

Derek does good work, and I wouldn't think it would be a problem with gears. If you think it may be the gears, give Derek a call and let him know. He stands by his work, and if there is a problem with his setup, he will make it right.

i dont think it is the gears... im gunna do a slip yoke kit and it should fix it. derek did do awesome work

Just to finish off this topic...

MUDNROX had the right answer. Pulled the rear diff. cover off and a couple of teeth from the pinion gear were laying there...

Working on replacing the rear end now...

Thanks for all of the help!