Just did the front wheel bearing - couple thoughts
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2005 S500 Designo
Just did the front wheel bearing - couple thoughts
The car has 230k miles, and it had a vibration at highway speeds that I’ve been chasing down since I got it. Little by little.
One of the early culprits I found was a wheel bearings in the front that were way too loose. I tightened them, and things got better, but if I tightened them to what mercedes considers appropriate specs (0.01mm), it vibrated at me angrily, so I loosened them. This left me with a front wheel that had a slight tendency to wobble. This was about 1 or 2 years ago, and I just got around to replacing them. Figured why tf not.
Couple takeaways:
There are 2 ways to do this, buy a hub with the bearings already in it, or buy the inner and outer races, the inner and outer bearings, and the wheel seals w/integrated speed sensor.
I did the latter way, but I would STRONGLY recommend doing the former. You will spend ~$200 more (based on AutoHausAz’s pricing), however you will save HOURS of work, you will SIGNIFICANTLY reduce the risk of ****ing things up, you won’t need a press, you won’t have part incompatibility bull****, and it will be much MUCH cleaner than putting all the parts together yourself. Also you get a new wheel hub.
I wish I wasn’t an idiot, but oh well. Now I know how bearings work.
Couple things: When replacing bearings you do both sides. You NEED a 0.001” caliper gauge. Harbor Freight sells one, it’s like $20, and it’s fine.
https://www.harborfreight.com/1-in-t...tor-63521.html
When tightening the wheel nut, you must hit Mercedes specs (the needle moves 0.001” (actually 0.0005”, half the distance between the marks). I would err towards 0.001” because loose bearings aren’t as bad as over-tight bearings. Mercedes says you can leave the brake disc on there. Bull****. Or maybe I have the wrong wheel bolt. Either way, when measuring from the hub vs measuring with the disc + hub, I saw about 10x as much play. Measure play with only the wheel hub.
If you’ve never done this before, everything I just wrote won’t make any sense, but it will once you look up the procedure.
One thing that is bothering me, my right wheel has a bit of a vibration/growling when turned by hand, and spins very very freely. I’m not sure why that is, maybe the inner bearing wasn’t packed with grease correctly. I have to watch, hope, and pray that it doesn’t manifest while driving. I didn’t notice it on the test drive, save for a very slight vibration sound that may or may not have been my imagination. As wheel bearings don’t ever get better, time will tell. I’ll keep a lookout for it.
If you decide to tackle the bearings yourself, buy 2 tubes of the green mercedes grease. It’s really good stuff. I think Febi is OEM. It’s about $10 a tube, and you will need 2 tubes. Amazon has a set of 2 for ~$20:
Regarding greasing the bearings, I’m not sure what the right way to do it is (again not an issue with buying the wheel hub assembly as I believe it comes pre-greased). I removed a lot of the old grease (that had turned black), but not all of it. I stuffed the inner wheel hub with grease so that when I stuck it on the axle, it oozed out, really packing that bearing full. No air bubbles. I believe that’s the right way to do it - the bearings will self pack as it heat cycles. I may be wrong.
Anyway, tl;dr: buy the wheel hub (P/N: 2203300725), not the individual bearings, races, seals, and grease. Buy a 0.001” caliber gauge from harbor freight. When tightening the nut, measure from the hub, not the hub + disc.
One of the early culprits I found was a wheel bearings in the front that were way too loose. I tightened them, and things got better, but if I tightened them to what mercedes considers appropriate specs (0.01mm), it vibrated at me angrily, so I loosened them. This left me with a front wheel that had a slight tendency to wobble. This was about 1 or 2 years ago, and I just got around to replacing them. Figured why tf not.
Couple takeaways:
There are 2 ways to do this, buy a hub with the bearings already in it, or buy the inner and outer races, the inner and outer bearings, and the wheel seals w/integrated speed sensor.
I did the latter way, but I would STRONGLY recommend doing the former. You will spend ~$200 more (based on AutoHausAz’s pricing), however you will save HOURS of work, you will SIGNIFICANTLY reduce the risk of ****ing things up, you won’t need a press, you won’t have part incompatibility bull****, and it will be much MUCH cleaner than putting all the parts together yourself. Also you get a new wheel hub.
I wish I wasn’t an idiot, but oh well. Now I know how bearings work.
Couple things: When replacing bearings you do both sides. You NEED a 0.001” caliper gauge. Harbor Freight sells one, it’s like $20, and it’s fine.
https://www.harborfreight.com/1-in-t...tor-63521.html
When tightening the wheel nut, you must hit Mercedes specs (the needle moves 0.001” (actually 0.0005”, half the distance between the marks). I would err towards 0.001” because loose bearings aren’t as bad as over-tight bearings. Mercedes says you can leave the brake disc on there. Bull****. Or maybe I have the wrong wheel bolt. Either way, when measuring from the hub vs measuring with the disc + hub, I saw about 10x as much play. Measure play with only the wheel hub.
If you’ve never done this before, everything I just wrote won’t make any sense, but it will once you look up the procedure.
One thing that is bothering me, my right wheel has a bit of a vibration/growling when turned by hand, and spins very very freely. I’m not sure why that is, maybe the inner bearing wasn’t packed with grease correctly. I have to watch, hope, and pray that it doesn’t manifest while driving. I didn’t notice it on the test drive, save for a very slight vibration sound that may or may not have been my imagination. As wheel bearings don’t ever get better, time will tell. I’ll keep a lookout for it.
If you decide to tackle the bearings yourself, buy 2 tubes of the green mercedes grease. It’s really good stuff. I think Febi is OEM. It’s about $10 a tube, and you will need 2 tubes. Amazon has a set of 2 for ~$20:
Regarding greasing the bearings, I’m not sure what the right way to do it is (again not an issue with buying the wheel hub assembly as I believe it comes pre-greased). I removed a lot of the old grease (that had turned black), but not all of it. I stuffed the inner wheel hub with grease so that when I stuck it on the axle, it oozed out, really packing that bearing full. No air bubbles. I believe that’s the right way to do it - the bearings will self pack as it heat cycles. I may be wrong.
Anyway, tl;dr: buy the wheel hub (P/N: 2203300725), not the individual bearings, races, seals, and grease. Buy a 0.001” caliber gauge from harbor freight. When tightening the nut, measure from the hub, not the hub + disc.
