It sounds like someone is beneath our Volvo, banging away with a hammer.

Dear Car Talk | Jan 01, 1998
Dear Tom and Ray:
daughters have been driving a '79 Volvo 242 DL for several years. Anyway, my
youngest just informed me that the car was making a strange sound. When I took
it out for a test spin, all of a sudden as I was accelerating, it sounded as if
someone were under the car between the front seats, banging for all they were
worth to be let go. I looked under the car, and no one was there! Any ideas? --
Judy
TOM: Well, it was smart of you to look under the car, Judy, because the first
thing I'd check for under these circumstances would be teen-age boys!
RAY: But since there were none there (or they gave up and let go before you got
back home), I'd have to suspect a bad center bearing. This is a rear-wheel-drive
car with a two-piece drive shaft. And where the two halves of the drive shaft
meet (right about between the front seats), there's a stainless-steel bearing.
TOM: That bearing is caged in rubber and attached to the bottom of the car with
a bracket. And when that whole thing wears out, the drive shaft can move around
enough to actually start banging against the underside of the car.
RAY: A new center bearing and rubber cage will cost you about a hundred bucks,
installed, Judy. And that should take care of it.
daughters have been driving a '79 Volvo 242 DL for several years. Anyway, my
youngest just informed me that the car was making a strange sound. When I took
it out for a test spin, all of a sudden as I was accelerating, it sounded as if
someone were under the car between the front seats, banging for all they were
worth to be let go. I looked under the car, and no one was there! Any ideas? --
Judy
TOM: Well, it was smart of you to look under the car, Judy, because the first
thing I'd check for under these circumstances would be teen-age boys!
RAY: But since there were none there (or they gave up and let go before you got
back home), I'd have to suspect a bad center bearing. This is a rear-wheel-drive
car with a two-piece drive shaft. And where the two halves of the drive shaft
meet (right about between the front seats), there's a stainless-steel bearing.
TOM: That bearing is caged in rubber and attached to the bottom of the car with
a bracket. And when that whole thing wears out, the drive shaft can move around
enough to actually start banging against the underside of the car.
RAY: A new center bearing and rubber cage will cost you about a hundred bucks,
installed, Judy. And that should take care of it.
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