My 2000 xj 4.0 Auto has an intermittent problem and usually in reverse.
The XJ will sort of bounce and hop in reverse but not all the time.
This happens in both 2wd and 4wd.
It will shudder while stationary in Drive but disappears on pull off. It will surge slightly in D as well. The transfer case lever rattles as they all do but more so with this shudder.
Now I do have a slight misfire at times, fault codes read bad number 4 injector and have ordered replacement upgrades. Difficult to tell if the missfire occurs at the same time due to the noise it generates.
I'm hoping this might solve it. Engine and transmission mounts are fine.

 

You make it sound like you just have a lead foot while taking off...

 

problem disappears with a lead foot

usually occurs in reverse at normal reverse speeds or slower. At standstill in D it rattles and shudders. On normal pull off it goes away -
Answer : Lead foot it no matter what?

No noise on idle in Neutral or Park - might get someone else to recheck engine and transmission mounts -