That your car sat for 22 years... to me just means that it has that many less original miles on it.. that's a good thing :-) (How many miles are on the car?)

Assuming there was no sign of rust pitting on the gears, I see no problem.

There are....lets see... 5 spots in there where gears meet up. And axle/side gear splines. A tiny amount of play in each one easily adds up to to ~1/4" rotational free play at the driveshaft... (that is what you said, no?). Doesn't sound out of the ordinary to me. The only way I know of to check it for sure would be with the appropriate measuring devices to check for appropriate free play specification.. as described in your green Volvo service manual.

I'm afraid that's something I can't help with... I've taken pumpkins apart, and I've put them back together... but I've never set ring and pinion gears. Can't help you there. I will say, I would think if there is a problem, you would more likely have some gear noise more than this clunk you describe.

I really think you should be looking at all bushings in the rear. maybe something loose in the brakes. The ring and pinion is the absolute last resort, as it is the most difficult to repair... And... if it is in the pumpkin, as long as you get no metal shavings or gear whine, it's probably good for another half million or so miles...



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-Matt I ♥ my ♂