W124 rear wheel bearings?

[ke6dcj]

I believe I'm hearing our 1988 wagon's rear wheel-bearings making a whirring/droning sound (not high-pitch, more of a low pitch).

What's the proper diagnostics and service? How much should I budget in parts?

Do I just replace the bearings? Do I do both sides? What else should I do (replace, service, inspect) while I have everything apart?

A good mechanic should take how many hours to do the job? Can a DIY do it without a press?

Also, is there an extreme/heavy-duty bearing that can go in it's place (perhaps from 1992 SportLine, 1995 E320 wagon, or 1992 400E/500E)?

Sorry for all the questions, but all my references are in storage while we're remodelling.

Thanks in advance,
:-) neil
1988 360TE AMG
1993 500E

[SocksE420]

My 88 TE needed both rear wheel bearing at around 100K (95K right rear, left 15K later). Noticed both noise and slack by shaking wheel - failed British MOT inspection. My mechanic said it was common, especially with wagons. My 95 E420 with 80K doesn't have any symptons yet.
Cheers, SocksE420

[Michael]

Could very well be the differential mounts/bushings-get them checked before you pop for the bearings. The diff bushings made the same sort of noise, but only when applying the throttle; ease off the throttle, pop it in neutral & see if noise goes away.

In my experience, when these bearings go, they get real loud real quick. Good luck Neil!

PS I doubt there are HD bearings-the ones in there are huge!

[mplafleur]

I wanted to ask the same question.

Now that my car is quiet (I fixed the exhaust), I can hear whinning in the back. It doesn't change on accel or decel, so I don't think it's the diff. This is a lower pitched sound that develops as soon as the car is rolling. I have also noticed that it goes away while turning to the right. I'm thinking tires, or wheel bearings. Any guesses?

[georgehifi]

I had the same noise, drove me nuts looking for the problem, tried everything, i almost gave up till i decided to do one more thing, i re-tensioned the rear wheel bearing nut and the noise went away, thought all was fixed untill it came back after about 500k`s now i decided to replace the wheel bearing itself. the old one had some chips on the running surfaces and the grease was quite dry and the surfaces and balls had a slight blue tinge to them showing they were getting hot. all is fixed now, btw mine is a 300e 87 124 150000k`s on it i`m going to do the other side also, i belive the life of these bearing to be around 200000k`s. also do`nt let any one tell you you need special tools to do the the job the bearings are an interferance fit and can be taped out and taped back in, it took me about 3hrs do do one side, now that i know what i`m doing the other side should take about 2hrs. you need to get the rear aligned after the job unless like me you mark the toe-in camber washers before doing the job and put them back to the same position after the job, good luck it`s time consuming but if your like me and do`nt trust anyone to touch your baby it`s very rewarding.

[per eriksson]

that tightens the bearing on W124 chassies?
Is it the same type as the one found on the wheelhub on W123 chassies?

You know the one with four sprockets that require a special socket to be used?

If it is I'm in luck cause I have my homemade socket hidden in the garage somewhere since the good ole days of a -80 300TDT.

[georgehifi]

normal socket fits this castel nut , for memory it`s something like 30 or 31 mm make shure it`s half inch drive because you`ll snap three eighth drive because the torque is something like 170 or such, check your Haynes manuel for the correct torque.

[per eriksson]

Aren't you talking about the nut on the outside holding the driveaxle in place?

That one is a 12point 30mm nut.

I figured it also are a larger nut on the inside that is accesible once the drive shaft has been removed.

Am I on the right track with this? I assume it is similar to the W123 chassie.

[ke6dcj]

It was definitely both rear wheel bearings. They were original and lasted approx. 155K miles. Not too bad, esp. since they are sealed and no real PM.

Make sure you get the one kit per side which is $10 more. Includes new bolts and the important giant circlip which is almost near impossible to take out with bending it.

All is quiet again.

:-) neil
1988 360TE AMG
1993 500E

[mbdoc]

georgehifi, you should work for MB if you can do a W124 wheel bearing in 2 hrs w/o any special tools!!!!

[ke6dcj]

2-hours for one side of a W124?

WOW! Even my best mechanic with the special tools was closer to 3 hours per side.

:-) neil

[Subman]

I know this thread is old but..

Is there any easy way you guys know of to check the wheel bearings?

My car is makeing that dreaded noise, but I do not know what side it is comming from, it is deff from the back though.
If I take the hub off and look at the bearing can I tell if it is bad?
It could be both rear bearings but I dont know, I only ordered one so I would like to do the correct one the first time

Thanks
Subman

[Kestas]

Subman, I work for a bearing manufacturer. The only way to tell if a bearing is bad is by either (1) A good, calibrated ear and feel, (2) A diagnostic tool devoted to detecting bearing noise, (3) A good visual inspection.

When you take the bearings apart, if they are anything less than perfect, they must be replaced. Most common defect is a spall. Other things to look for are tiny (or large) dents in the raceway, corrosion, brinelling, raceway frosting, bent or broken cage, or discoloration (blue or black) from heat. Any of these conditions require bearing replacement. Bearings must be replaced as a set, not just one race. They must be kept as a matched set (no mixing parts among like bearings). If one wheel has a bad bearing, it's not necessary to replace the bearing on the opposite wheel if it's still good.