My experience is limited to u-joints so let's assume for the moment that's what we are dealing with.

I would have to hear the noise you're describing. It may or may not be related.

I don't know how to answer your second question other than to say it's just physics. What I don't understand is why you don't have this on first accelerating.

The best way to examine the u-joint would be on a garage lift but I suppose you'll be doing this at home so please take all necessary safety precautions. Chock the front wheels both in front of and behind them. One of the rear wheels also. Set the parking brake and put the car in neutral. Raise the other rear wheel. Support that side of the car with a jack stand under the axle tube. Now release the parking brake. Rotate the raised wheel and observe the u-joint at the differential. If the u-joint is bad the end of the driveshaft will be in an eccentric orbit around it's normal axis. If the driveshaft rotates normally on it's axis you might want to take a close look at the u-joint. A dry joint may have rust emerging from under the bearing caps.

I apologize for the condescending safety lecture. It is done just in case you are new to this sort of endeavor. Please be careful when working around or under a raised car.


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'79 242, '84 DL 2 door, '80 DL 2 door, '89 DL Wagon, '15 XC70 T6 AWD