I posted a few days ago that I have a 122 for sale and the potential purchaser declined the car after driving it, saying he thought the rear end was bad. The car makes a pulsating noise under power--no knocking or thumping, but increases with speed. The flange bolts are tight, center bushing and rubber recently replaced, and I believe all the U-joints are good.

I pulled the housing off the rear end and don't see any bad teeth or chips of steel inside. It does seem to have a fair amount of play, but I don't really know what is normal. Now the questions:

1) Could the pulsating sound be caused by a bent or unbalanced drive shaft?

2) How much play should exist in the rear end?

3) Can I put the rear end from a '73 1800 in its place?

4) If so, do I have to replace the entire rear axle or can I just put the guts in and retain the drum brakes?

Remember I am trying to sell this car. I don't want to invest a huge amount of time or money in it, but I do want it to be solid when I sell it.

Thanks!

Tim