88 300E Center Bearing noise
 

I've noticed a slight sound like a bearing growl lately coming from the rear of the car. Is this a symptom of the center bearing going bad? No vibration issues. Took a look under the car and saw my front rubber driveshaft connector is perished and rear trans seal looks to be leaking so ordered those parts and a center bearing and support as well but wonder if I need to replace it. Just 70K miles on the car.

I've never heard a center bearing make enough noise to be heard in the cabin, but if the rubber is gone, it probably could happen.

Let us know what you find.

I'm going to put the car upon jackstands and run it through the gears and see if I can isolate the noise. Also will check rear diff fluid as well.

Rear wheel bearing also a possible culprit.

That's what I was thinking too but only 80K miles.

Replaced the front rubber driveshaft connector today and listened to the center bearing with a length of hose to ear while the rear end was up on jackstands and the front end on ramps. Didn't seem to make any unusual noises. Afterwards I took a test drive and I still hear the same sound, like the rear tires are snowtires. No rear wheel bearing play that I could feel. Again, only 80K miles on the car.

Possibly the best way to isolate is to use chassis ears (clip on mikes) while road testing. With 80K and 24 years, I'd say your bearings have had ample opportunity to deteriorate. Mine went bad around 100K and just droned for a year with no other symptoms.

I'm kinda suprised they wouldn't have lasted longer, if indeed it is the RR wheel bearings.

FWIW, I believe I'm still running on the original RR wheel bearings. 135,300 mi. on the clock. 88 300CE. Dunno if it matters, but always dealer serviced (at least for the last 11 years:o) and always garaged. Hope you find the problem.

To determine a rear wheel bearing , drive in a slight curve at 35-45 mph ,lean car over in a turn , and hear if noise changes, it will be louder
going left/ right , what ever side you unload , if it gets quieter thats your side with the bad beaing, you may be able to feel looseness in that wheel but usually not , that bearing is a double row of round bearings.

No sound change around corners. Maybe it's not the rears, maybe it's the center? Does the center bearing have a shorter lifespan?

I recently did my center support bearing, i had a bearing noise kinda like an old jeep stickshift whine type noise , it was louder in reverse, thought all along it was trans, after i replaced it, it was completely quiet, started to hear noise when it first was going out as a high pitched whine easy to do, used press after splitting driveshaft, my car is 94 e320