HOWLING... but just some time - PeachParts Mercedes-Benz Forum

macthomas · #1 11-04-2005, 09:41 PM

Has anyone else had this problem?

About 3 days ago I was driving my 87 300SDL and I heard a howling sound. I could feel the vibration in the accelerator. It quit for a day and is now back, but only when I am going between 25 and 40, accelerating, and I am drifting (slight turn) to the right. It is coming from the front of the car... maybe drivers side, but I can't tell for sure. Kind of a WWWWHHHHHHRRRRRRRRRRRRRRRR sound high pitched.

I know I need to replace my tranny mount and motor mounts. MB guy said they are in need of replacing. Could this cause it? Brakes are new, tie rods new, steering shock new.
Any ideas
Thanks

t walgamuth · #2 11-04-2005, 11:51 PM

could be. could be the fan or some other moving part rubbing on the fan shroud or such.

better fix those mounts. it could be rubbing on your oil cooler lines. you dont want to lose them. your oil will spill out faster than you can think of it.

tom w

jaoshea · #3 11-05-2005, 12:37 AM

Also check front wheel bearings. Rt turn loads left front wheel bearings. Do the mounts-make a big difference.
good luck

Maki · #4 11-05-2005, 02:08 AM

Quote:

Originally Posted by macthomas

Has anyone else had this problem?

About 3 days ago I was driving my 87 300SDL and I heard a howling sound. I could feel the vibration in the accelerator. It quit for a day and is now back, but only when I am going between 25 and 40, accelerating, and I am drifting (slight turn) to the right. It is coming from the front of the car... maybe drivers side, but I can't tell for sure. Kind of a WWWWHHHHHHRRRRRRRRRRRRRRRR sound high pitched.

I know I need to replace my tranny mount and motor mounts. MB guy said they are in need of replacing. Could this cause it? Brakes are new, tie rods new, steering shock new.
Any ideas
Thanks

Just a wild thought -- I had an Audi with a bad center driveshaft bearing that produced an incredible howl (carrier was OK). I only heard it from 25 to 40 mph. And it would come on suddenly, like fine one second and howlllllll the next. It was a deceptive sound while driving...it took an accomplice with a stethescope to determine the source.

As for the trans/motor mounts, he could be right but I can't think of anything that bad mounts would do to produce a *high-pitched* howl. I'm no W126 expert, but on the W123, bad motor mounts produce a buzzy vibration at idle and, more ominously, can put the oil cooler lines into dangerous proximity with the accessory belts.