04 E55 AMG: Front end clunk

[kevm14]

Here's a list of stuff for my NC trip:
- Investigate front end. Probably do thrust arms assuming my check doesn't cast doubt on that conclusion.

I can't seem to escape clunks I guess. I tried inspecting stuff. I tried dropping the front on its own weight (first ramps, and then wood). I had Ian steer while I checked stuff. It didn't clunk very consistently but when it did I could not locate the source of the noise.

I am not sure the thrust arms are bad. The upper ball joint boot on the driver's side seems somewhat compromised. So this has been inconclusive.

It is possible the clunk was more on the steering column side but I need more inspection time before I could possibly chase anything. So not ready to order thrust arms yet.

[kevm14]

I am considering doing the upper control arms.

Video from a W211 coil spring car. My car will be harder because the air bag is huge.
https://www.youtube.com/watch?v=gSM3rUDb8_g

May go with FCP Euro for these:
https://www.fcpeuro.com/products/merced ... 2113308907
https://www.fcpeuro.com/products/merced ... 2113309007

$113.69/ea.

[kevm14]

At least my hunch was right! The bottom did seem fine.

Here we go.
https://youtu.be/JQrlq5bNJbY

Conclusion: needs wheel bearings adjusted and the front bushing on the driver's side upper control arm is totally shot. So I ordered a pair of UCAs ($113.69/ea). I even found my Mitutoyo dial indicator and magnetic base! I can play real mechanic now, baby.

[kevm14]

Got my arms.

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[kevm14]

Time to adjust the wheel bearings and rotate the tires. I'm glad I rotated (side to side) because the tread looks quite scalloped. Way overdue.

Attacked the driver's side first. Pulled wheel for the first time. This allowed me to inspect the pads.

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Tons of life left on...the four pads. Geez. Look at the size of that caliper compared to my hand.

With that done I popped off the wheel bearing dust cap and got out my dial indicator.

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This was slightly disappointing. Despite clearly rocking and making a clanking noise, the axial runout appeared to be within spec. I was able to just barely snug down the bearing adjuster but it was a very small amount. I think the rocking play did decrease a little. Onto the right side.

This one had a LOT of play. Both rocking AND axial play. It looked like several times the spec. Good news? Not so fast. I tried tightening it and it got hard to turn but there was still a ton of play. Uh oh. Yeah, gonna need new wheel bearings. Obviously I'll do both front bearings.

The brake pads looked just as good as the driver's side at least. And again I did rotate the tires. But I'll have to order two pairs of bearings and grease seals.

That job is fairly simple. From memory:
- Unplug SBC pump because opening a door primes the brakes and could possibly launch the pistons out of the caliper or something....
- Unbolt caliper and hang safely (thing is massive)
- Remove bolt holding rotor to hub and remove rotor. Hopefully they aren't stuck.
- Unthread bearing adjuster all the way and pull hub off the spindle.
- Remove grease seal, remove bearings, hammer out inner and outer races. Clean stuff.
- Hammer in races.
- Pack bearings.
- Install bearings.
- Install new grease seal
- Slide on spindle
- Thread on adjuster
- Probably put rotor back on so I have something to grab
- "Overtighten" adjuster to set the bearings, back off and then fine tune with dial indicator.
- Install dust cap
- Install caliper
- Done?

So yeah I need bearings, seals and I guess grease. Should I get the OEM green Mercedes grease? Probably...

[kevm14]

Ordered Mercedes inner and outer bearings, seals, Mercedes grease and new dust caps. $206 all in from Pelican Parts again. I did the economy shipping (ships from CA) so we'll see what happens.

This was approximately 3x Rockauto prices. 3x Rockauto for OEM isn't all that bad I guess.

In retrospect what I should have done was gone with the SKF bearings on Rockauto and the rest Mercedes and I would have saved $88....whatever.

[Adam]

One of these days you'll have a daily driver that doesn't clunk.

[kevm14]

I think I am close based on my findings. Plenty of smoking guns here. Of course these cars have 1 million links, ball joints and bushings so....

[kevm14]

Leaving this here for my wheel bearing job.

https://mbworld.org/forums/w211-amg/549 ... ights.html

Evidently the wheel seal has the ABS reluctor built into it somehow. And driving the seal past flush in the hub creates too large of a gap to the wheel speed sensor and you get codes. Good to know. Hope I can handle installing the seal flush. Because past flush and I'll destroy the seals removing them only to have to start again.

[kevm14]

Tackled the driver's side first because it should be the hardest. Yeah.

First I had the bright idea to see if I could simply "flop" the front SAM out of the way. I worked at it for like an hour+ and pulled everything apart but the SAM compartment is still sort of stuck in there. I'd have to screw around with more wiring to pull it out. So instead I just said let me put the car in the air and work on this and if I still can't reach the nut I guess I'll reassess the SAM idea.

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Well, I got it apart without the SAM being in the way. Great. Now I have to deal with that. Good news: now I know how to replace the SAM. Hope everything works properly when I put it back together. SOOO many electrical connectors and stuff. It would be easy to miss one. Or three.

Managed to precariously lay the shock on the rotor. I say precariously because I was too lazy to remove the wheel well liner and unplug the shock. So instead I thought it would be smart to risk damaging the wiring on the shock. Anyway I got the old arm out. Initially it all looked fine but if you put a little twist on the sleeve it reveals a crack in the bushing. Just goes to show you can't always rely on a simple visual inspection. It's not like chunks of bushing are missing or something.

I also lost a nut. I spent way too long setting up my impact when I should have just used hand tools and buzzed the nut off so fast that it fell down into the engine bay somewhere. It's probably just laying on one of the under body covers. So I'll have to get down there and pull one off to grab the nut. Hopefully reassembly isn't too bad. I will have to position the arm properly when I torque. I will also have to carefully get the nut started on the bolt. I will do this by holding the shoulder nut in the box wrench down near the bolt and turn the bolt until the threads start. Then I should be alright.

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What I think I should do is see if I can get a long 16mm offset box wrench. Just having a longer one would make this easier. So again - the car is designed alright. I did not have to touch the SAM. But you are expected to have a variety of different tools for different situations. You have just one length 16mm wrench? Pffft.