I also had some banging noises, similar to the hammer on wheel sound.
I dunno what exactly was wrong but I pulled off the rear wheels, pulled the
drums, cleaned them, and loosened the rear brakes a bit.
There was a good deal of buildup in the drums, but with everything cleaned
up, no more banging. ; )

Eric Nettles
87 Wolfburger

  I just had a similar experience with my '91 GL. It turned out to be the CV
joints in the rear. There was no grease (or whatever lubricant is used) left
in the boots. This noise was also more prominent at low speeds and sounded
like someone hitting the wheelwell with a hammer. Very alarming noise
indeed, and it seemed to come and go for a few months until it got really
bad. Hope this helps!

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