I have a problem. I had a knock in the rear when i was up/ down shifting2nd to 3rd 3rd to 4th ect ect. I also have some slight vibration while driving.I just had my ring and pinion replaced, as well as all the bearings involved with changing them. There doesnt seem to be any play in my rear driveshaft anymore. I did not replace the ujoints yet. I'm running 4 inches of suspention lift, AMC 360, t-176 4spd, dana 300, AMC 20 with POS 2 piece axles, 33x12.50's. Is it the Ujoints? if so what is a good brand to get? Or is it my POS 2 piece axles?? I dont know how to tell if its the shafts. Hopefully its just the Ujoints. There is no cv joint, or axle shims in the rear. What should I do next? I'm getting tired of spending money on unbroken parts. Ack. Isnt jeeping great? What should I look at next??
I dont think its the trans but i guess it could be??
I forgot to say also that I replaced the transmission mount. When i had someone else drive the jeep, when they shifted the entire rear axle rotated up, then back down, i was told the bad tranny mount made it do that. But i havent been able to verify that the new one fixed that because i havent had someone else drive the jeep so i could look at it. So if its still doing that then maybe that could be causing the clunk. Also, it only clunks once when you engage the gears.
The upward rotation of the rear end is know as "axle wrap". It's caused by torque and a leveraging effect on your longer springs. (longer arc due to the lift) The only way to cure it is to attach another link to the axle to keep it from trying to rotate in the opposite direction of the tires. This is, however, counter-productive if you're into the articulation thing. The "clunk" could be the result of the axle comming into contact with something while its dancing around under your rig (muffler, shocks, etc.) It could also be the U-joints as suggested in the previous post. I strongly agree to get "good" ones. I buy a lot of parts from the chain stores, but their U-joints aren't one of their better items. I just got a set of heavy duty servicable ones from NAPA for $15. Good luck finding the noise - watching and listening while someone else drives is probably your best bet.
Another 7 by "CJ's Heaven"
Well I figured out the problem. My U-bolts way undetorqued. You could acutally see through the leaves. I was reading how they're supposed to be 100 FT-lb so i got under there and checked them out and they were probably 5 ft-lb! So I tightened them up and now i'm fine. I did pick up some universals to through in there too because there is some slight vibration now. But the knocking is gone.