Clunking when shifting into drive or reverse...

[Sodium Duck]

When I shift into drive or reverse, I get a minor clunk/lurchy kinda of sound/movement. 700R4 tranny.

I happen to be changing out my driveshaft ujoints, so I have a chance to play around with the pinion flange on the rear axle. I know there isn't really a spec or measurement for backlash, unless I pull the diff apart... but I can rotate the pinion flange probably a good inch or so. It does not move in any other direction. I can not budge it in or out, side to side even if I try to move it that way. It just rotates. Is there a certain way it should feel? Am I over reacting? Is there anything else I can check at this point with the drive shaft out?

[Fairlane514]

Its probably your U joints, so see what it does after you change them.

Backlash and improper gear tooth engagement will result in a whining noise. If you didn't have enough preload on the pinion (you can measure with an inch pound torque wrench, wheels off) you would probably hear a whining noise as well.

[clay7]

throttle pressure could be set too high on your trans

[slammed79]

I'm gonna agree with fairlane and add you may want to check your transmission mount while you're under there.