When I accelerate there is a grinding or groaning noise(med to low pitch), and a very slight vibration noticeable directly under my feet and slightly towards the front. When off the gas, its dead silent. The more load and the more I press the throttle, the worse it gets. Seems more noticeable in overdrive and at lower revs/higher speeds. Removed the front driveshaft and still there. Going to remove rear today and test that. My gut is telling me the rear driveshaft, but last time I had one go out it sounded like a gattling gun, even at lower speeds with throttle only.

4.5"lift w/ SYE, corrected front and rear pinion angles, 33" tires, new front and rear drive shafts, new gears.

Any ideas?

Thanks

 

What year? Manual or auto?

 

00 Auto

 

Inspect your motor mounts and this area here:

 

Double checked all mounts and all looks good, they only have 10k miles on them. Exhaust is solid, no evidence of hitting cross member. It's sitting a good 1 1/2 inches away. Checked the mechanical fan and shroud as well, looks good. When you are on the gas is there "driveline" noise? Is there a difference between on/off throttle, noise wise for anyone else? Maybe I am being too sensitive to noises, but there is definitely a low deep groan "urrrrrrr" only present on throttle. Feel it in the floor board directly beneath driver seat. Taking rear driveshaft off now and replacing with spare to test. Might check/change the tcase fluid, although it's only got 5k miles on the new fluid.

 

Hey did you ever figure this out, did the same lift and am hearing a sound and feel that slight vibe under my feet. Thanks

 

When looking for rubbing, know that the engine will tip to the right (pass side) under acceleration a decent amount. The older and softer the mounts, the more it will move. In a static state, you are looking for smaller clearances. Best way to test is to have a partner step heavily on the brake and give it gas. This will cause the engine to move and can examine possible contact points.

Larry