I had the exact same issues after lifting my 97, only I had lifted it a bit more (RTE 3" which was more like 4"). Usually 2" doesn't screw stuff up, but each truck is a little different.
The lift and resultant driveline geometry changes brought up two issues for me, either of which might be your problem:
1. (Most likely) - The stock cv joint driveshaft is banging at the extremes of it's joint articulation when you release the throttle load and the truck's weight shifts forward a bit. - I fixed this by correcting rear driveline angle using modified trailing arms (and caster-correcting radius arms for the front, too, along with a front double cardon driveshaft)
2. My diffs were starting to go, and the change exacerbated the gear lash "feeling".
I wrote about this stuff in one of my old posts.
'86 D110 3-door
'97 D90SW - SOLD SEP '14
'94 D90ST - SOLD MAY '13
D90s sold while assigned overseas. You're welcome America!
'06 Range Rover Sport Supercharged
'8X FankenRover D100