Outer Limits 4x4 Board

I have a 92 Landcruiser and when driving if i let up on the pedal, then step on it again i will hear and feel a clunk. It is a little worse after i have driven 2 or 3 miles. I had 4 new toyota u-joints installed thinking that would help, but it did'nt. Anyone have a idea of where to look next.
It only has 91K

The 80's do have alot of driveline "slop" in them .. but i will leave it to the experts to diagnose ..

If its a constant 4WD (backlash problem common) it will most probably be the drive splines on the CV's and the hub drive flange internal splines. These splines wear and loosen the connection between the two and cause the backlash. When you hear the clunk its allready stuffed and 9 times out of 10 you will find the RH worse than the LH. Remove the small grease cap in the middle of the front drive flange jack the cruiser up with it in gear and turn the wheel back and forth and you can see how much wear there is. Sometimes by fitting new drive flanges it can help but if its clunking as you described the spline on the CV will be shot as well. Bottom line new CV's and driveflanges is whats required.
Wally

Adding to 80 utes comments, the rear driveshaft can get slop in the spider splines after high miles, and the front c/v's become worn where the balls contact the cups, so there are many places to check, and the best way is to have it in neutral with wheels chocked, and have a play around under there while you grease everything.
Good place to start is the front wheel drive plate splines as discussed, after that rock back and forth the front shaft noting amount of movement, then compare it to the rear shaft. Now it is usually a bit more in the front, but if you are turning it 1/4 turn then things are worn bad, and it is time to consider your options....loka, new c/v's and drive plates.
Andrew