i was on a drive about a hour and a half out of where i live and when i started to drive agine i get this klunk in the rear pass side. i just did a rear brake job and did what the book said to the T and now after a long drive i have a vibration and a sort of klunk in the rear end. o dose any body live in the killeen/fort hood area?

Have you checked your lug nuts? That's the only thing that you would loosen and tighten for a brake job.

Z mid to rear clunks are often hard to trace and often multi-symptomatic (requiring a few U-Joints, Bushings, bearings, Mounts, bolt tightening). Does the problem happen on shifting, braking, throttling, hitting road bumps, when playing Parliament Funkadelic....

For local support, check out http://czot.org. Austin Z-Clinic is about an 1.5 hours away.

Silvey, jack the rear of the car by placing the jack under the diff pumpkin. Now try lifting and lowering the pass. side strut assembly. I suspect the rubber top strut insulator separated/got torn. It happened on my 76 and was making the clunking noise you described.

It also can be attributed to the worn diff member top brace. Do a search for a Ron Taylor (RT) differential mount mod. But like GreenZ said, there might be quite a few causes.