Hey everyone, I'm stumped by a low pitched intermittent whine at low speed from my '87 240dl wagon. It doesn't seem to be mechanical. I first thought it was automatic transmission whine, but it does it in neutral while coasting.
I wondered if it was snow build up on the roof making the roof rack sing. Snow's gone, it still sings.
This is my first brick and wonder if anyone else has encountered this.

BTW, I still love the Yokohama Avid touring tires that I bought after asking advice in this forum. We've had some heavy wet snow on icy streets and the tires make me think I'm driving an AWD. Thanks again to the collective wisdom of this list.
Steven

Thanks for the great advice, Iroll, I had the bearing greased and it is now quiet and all is well.
I'd have done it myself, but no garage and winter in Indiana makes me lazy.
Steven

This may be the hanger bearing in the middle of the driveshaft. If it appears more at cooler temperatures, varies with the speed of the wheels, is only present when the car is moving, and the hanger bearing has never been changed, then it is likely the culprit.

You have some options:

Most expensive: Replace the bearing (worse still, have it replaced)
Cheapest: lubricate the bearing
Unwise: do nothing

To lubricate, safely jack the car and put one end on stands (or raise it on a hoist). Use a hypodermic fitting on a grease gun and inject some grease into the bearing by putting the needle in under the outer edge of the dust cover between the inner and outer race of the bearing. No disassembly of any kind is required. Results are immediate and can well last several years (then repeat the process). Total time required, including jacking, finding tools, clean-up etc.: about 15 minutes. Cost: nil
--
'61 122s B16, '67 122s B18, '76 245 B21F, '81 245 B23E, '90 745 B234, '95 960 B6304 (not counting parts cars)

One likely suspect is the drive shaft center support bearing.

My '86 245 sang to me for several years before I finally swapped out the bearing.

In other words, if it is the bearing, it's not life threatening....
--
Don Foster (near Cape Cod, MA)