If I take off hard from a stop or go for a heavy acceleration I get a noise that is between a grinding and a vibration. Drive shaft u joints look fine..there is no play in them. You can almost feel the grind/vib basically right under the seat. It doesnt do it when in neutral..so its not in the engine..only under power. Did some reading..maybe its the tranny mount? Could be a u joint i imagine but I dont feel or see any play in them.

00XJ 92k Auto Trans..

Thanks in advance.

Anyone?

How highs your lift?

Just a little 3 inch. It will be a 4.5" 3 link with a HnT in about 3 weeks though..
Currently have a tc drop on it...that will obviously be eliminated with the HnT.

Also may be important to note that I get an occasional slamming into gear as if I was parked on a hill.. Typically only happens going from Park to Reverse.

Look at the exhaust pipe above the trans brace see if its hitting anything and look at your trans mount i have the same problem and mine is the trans mount and the bracket that holds the exhaust above the mount was broke so i had to weld it back in place

Ill take a look at it today or tomorrow. Hopefully its something stupid like the mount.

If it turns out to be the trans bushing change it with the polyurethane 1 don't go with stock polyurethane bushing will run you about 50 maybe 60 bucks a stock 1 is about 100