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I have been experiencing a high pitched humming sound coming from my passenger rear (I think...it's a little hard to tell) when under 40mph and coasting or braking. Sound does not change when I apply brakes or emergency brake. Doesn't really change pitch as I slow either. Then it stops when I stop. Hum doesn't present as I accelerate. The sound goes away in the rain and comes back promptly in dry weather. That last one is odd...anyway.

In talking to people here and there, consensus says its my rear wheel bearings. However, just the other day I talked to another guy who made a good argument that it could be the pinion bearing where the drive shaft goes into the diff. Of course, I had already ordered the bearing kits when I talked to him. Could be either I suppose. I am going to do the passenger rear first and see if the sound goes away.

There is a great DIY by Dmorrison in the PeachPartsWiki for this job. I will try to take some pics as I do it so we can have something here at BW.

I did as much research as I could on bearings. Not a lot of definitive information out there so in the end I decided to go with genuine MB. Usually you can't go wrong there. I was under the impression that SKF was the genuine bearing supplier for MB. I did find a lot of information about SKF's being counterfeited in China...so much so that SKF has a web page dedicated to it on their corporate site. Skip them...

These bearings are made in Hungary by F.A.G. Hopefully this company is on their game. They seem to be well liked and a long time supplier to MB.

Cost from parts.com was about $92 a side plus shipping. Apparently only 1 special tool is needed. Got that from the local dealer for $125. There were other suppliers for much less, but, I read about fitment problems on the internet. Again...when it doubt, clean your wallet out with genuine MB. I will proudly loan it out when I am done with it so others can save the ass-raping on that tool ;)

Any advice is welcome.

I know everyone likes parts pics!!

Boxes:



Contents of box. Special socket tool on lower left:



Pic of 1 of the bearings:

 

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Just about any of the European bearing mfg's make a good product, certainley FAG does. I'm sure the Chinese bearing is fine too, but I agree the European part is a better bet.

Very generous offer on the tool. Good luck with the job!
 

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that job is a PITA... FAG's are Fine...chinese bearings are Such crap it's spectacular.. you might get a year or two max out of a set...pathetic.

Jonathan
 

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Wow, if you think its a PITA, I am in for a real treat. Tomorrow I should have all the tools I will need and I will tear into it.
 

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Do you have access to a car lift or jacks? Raise the car up and rotate the rear wheels. Do you hear grinding? When in gear on the rack or jacks (PLEASE BE SAFE), listen to the wheels. This should give you the answer.
 

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Wow, if you think its a PITA, I am in for a real treat. Tomorrow I should have all the tools I will need and I will tear into it.
foolio2, did you ever complete the job?

I have a rear wheel play and i was told it is the rear wheel bearings. called around for quotes and most shops do not want to touch it. :crybaby2:

just wanted checking in to see how it went with you and if you had any advise. thanks!
 

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SKF a good brand?

Are SKF bearings made in Europe (says it is in MANY countries)? Anyone used them? Might get the front and rear bearings done soon.

thanks!
 

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SKF are hit or miss...I've seen mexico, brazil etc..

If you REALLY want to be sure you're getting good bearings these days get Genuine.

Jono
 

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SKF are hit or miss...I've seen mexico, brazil etc..

If you REALLY want to be sure you're getting good bearings these days get Genuine.

Jono
Thank you - I appreciate that advice. I will go for genuine!
 

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Since this is a job you really only want to do once, I go along with Jono on getting original bearings. FYI, you will HAVE to have the "special tool" in the top picture. I had to use my 1/2" Impact Gun to get the retaining ring out, and then back in. There is a crush ring that sets up the bearing run out and that tool is the only way to get enough torque onto the retainer to crush that ring. Once I started the crush ring deforming, I could then use a BIG ratchet wrench to get the last bit of crushing done for the correct run out.
 

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Since this is a job you really only want to do once, I go along with Jono on getting original bearings. FYI, you will HAVE to have the "special tool" in the top picture. I had to use my 1/2" Impact Gun to get the retaining ring out, and then back in. There is a crush ring that sets up the bearing run out and that tool is the only way to get enough torque onto the retainer to crush that ring. Once I started the crush ring deforming, I could then use a BIG ratchet wrench to get the last bit of crushing done for the correct run out.
What is the range for cost having it done at an indie shop/dealer? I am incompetent when it comes to DIY. It took me 3 hours with a buddy to install euro headlights.
 

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do bearings despite no signs of trouble?

Is there a benefit to getting the front and rear bearings done even though no signs of a problem exist currently? I'm familiar with bad bearings - but after 22 years, 85k, would I see an improvement with driving if I do them?

Looking for justification to do them...there might not be any!
 

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Discussion Starter #14
Honestly, I don't see a reason to have it done just to have it done. Unless, you derive some satisfaction from that peace of mind. My rears lasted 150,000 miles and I'm still going on the original fronts.
 

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Thanks - sounds like no benefit or change in experience if I had them done now. I'll prioritize other things! Thanks again
 

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You can inspect the fronts for your own piece of mind, but the rears just let be until they show decided signs/slop for you to replace them..
 

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I've had the rear bearings go out on a pick-up truck. When this happens you hear/feel a grinding crunching noise when moving and will want to get it fixed like right now!

Bearings can be a bit loose with age and they can be snugged up / tightened. If loose the wheel can wobble a bit and vibrate at higher speeds. And only do that following the directions in the factory service manual. They need to be tightened and then loosened a tad - to leave room for the bearings to heat up and expand a bit.

The front wheels can have wobble and play in them from other worn parts like tie-rod ends. You can jack up each wheel and see if you can wiggle the wheel.
 
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