My 1984 240 DL wagon recently started vibrating/shuddering like crazy, but
ONLY between 40 and 50 mph -- keep below 40, or above 50, and it's smooth.
The vibration stops, even between 40-50, if I take my foot off the gas. The
rumble sounds from the rear.

My best guess is out-of-round tire. I recently had a tranny rebuld and an
alignment (but all was fine for a few weeks after each repair). Anything
to consider other than bad tire?

In article <185d2f689ad4a3ba491f0fbbf72bb548 (AT) localhost (DOT) talkaboutautos.com>,
naverillsn001 <eaveril1 (AT) tampabay (DOT) rr.com> wrote:
Could be a drive shaft imbalance--presumably, the shop knew to keep the
two pieces of the drive shaft aligned.

Check the support and support bearing as well.


Gary

--
Gary Heston gheston (AT) hiwaay (DOT) net
The Intel ASCI Red supercomputer placed first in the 11/97 list of
the top 500 supercomputers in the world, at 1.338 TeraFLOPs max.
As of 6/05, it wouldn't make the list.

"naverillsn001" <eaveril1 (AT) tampabay (DOT) rr.com> wrote

Check the U joints on the driveshaft, my brother's 240 started doing that
and one of the joints had lost it's needle bearing completely.

Thanks very much, folks. My Volvo guy replaced my U-joint ($120), and all
is well.

You good folks saved me from buying tires for nothing. :-)

Thanks again.