Hi all,
Coincidentally I also have a wheel bearing question but it is for the rear DS wheel.

Symptoms:
I have a roaring sound that increases with speed (RPMs) and when I get out of the car there is a creak that sounds like a weight has been taken off the DS rear wheel.

History:
I had both front ball joints and the left rear axle replaced in November. (I need a wheel alignment!)

Drove a 500 mile trip before Xmas, then on the return trip began to hear the noise. I had to go back again (family emergency) 36 hours later and during that trip the noise at high speed was very very loud.

Today:
I have to make the return trip in a couple of days and wanted to find out what's causing the noise before I get back on the road. Had an Indy drive it to see what he thought. First he said tires, then he said "probably bearings" (but would have to take the axle apart to be sure).

Dealer is pricing the bearing kit at $125 and labor at $460. The indy won't quote on labor until he looks inside the axle.

I don't make a move without checking with this forum first-- so what do you all think? Any opinions will be appreciated!

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k. darkman
1987 300D Turbo 200k

The rear bearings are not really a DIY task because of the special socket required.

4 Hours at $115/hr ($460) is quite a long time for a dealer. The indy should be a bit lower.

Be sure to have the indy put his quote in writing before any work is done.

What special socket is required for doing a rear wheel bearing job? My W123 needs rear wheel bearings, is it a special tool I need to buy, or can I make it from a tool I already own?

If the tires are worn enough to have the wear bars flush with the remaining tread pattern, the car will be noisy and have some vibrations that can mimic a bearing noise. Also, since it is winter, I would be inclined to replace a tire with wear bars showing across the remaining tread.

If the wheel bearing is dying, there should be noticeable play when you jack the car up so the tire is off the ground and you shake it in and out, or cock it on the shaft stub. Check this with the wheel and bearing cold. If the bearing has play, you can try adjusting it. Do a search for setting the wheel bearing play, or check the manuals. If there is any serious damage, this won't do much good.

I would also suspect the CV joints in the rear axles. I know you said you just replaced the driver's side, but they also make a noise that can mimic a wheel bearing as they wear out.

Good luck, and try to find and correct the problem before getting on the highway for a several hour drive. Jim

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Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)

http://www.samstagsales.com/mercedes.htm
M0027
115 589 02 07 00
915 589 02 07 00
Pin Wrench Socket. For R&R of the grooved nut on the rear axle shaft flange, or when replacing axle bearing and seal. W107, W114, W115, W116, W123, W126.
$64.95

Attached Thumbnails

 

You can rent that socket from the tool rental forum........right on this site.

It can also be bad by having a clicking noise when turned. Remove the axle from the hub to isolate it from any possible axle joint noise.

Thanks everyone. I have to wait until daylight to check most of the suggested checkpoints, but I did go out to look at the tires.

My DS rear is definitely the worst and the tires are 2 years old. Regardless of the fix, I can see that it's time for tires! I've probably been 'getting by' because of the mildness of the winter (so far). The quick 2K on the highway may have been the last straw for them.

If you guys think of anything else, please let me know. I'll be taking all of the suggested checks to the indy in the a.m. AND will definitely get the quote in writing before any work begins.

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k. darkman
1987 300D Turbo 200k

I had the wheels checked and the indy said the bearings looked fine and that there was no play in the hub that would indicate a problem.

He said I needed new rear brake pads and that even tho they weren't worn enough to trigger the warning light, they were thin enough so that the vibrating (roaring) noise could be caused.

Does this sound reasonable to anyone?

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k. darkman
1987 300D Turbo 200k

If they are thin they need to be replaced anyways. Start cheap work your way up.

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http://superturbodiesel.com/images/sig.04.10.jpg
1995 E420 Schwarz
1995 E300 Weiss
#1987 300D Sturmmachine
#1991 300D Nearly Perfect
#1994 E320 Cabriolet
#1995 E320 Touring
#1985 300D Sedan
OBK #42

but he has a w124. that tool isn't used on the rear bearings.

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punkinfair