cmpcpro

Yeah I noticed your thread. That looks nice! I'm not ready to go that route though.. maybe I'll stick the borescope up there to check. How did the top of your struts look? If they are just lying there and it's not too much trouble maybe you could snap a pic so I know what I'm looking at.. if not I completely understand you've already been such a great help I don't want to ask too much.

g60wall

I'll send pics tomorrow morning they were crack And they were only 3 years old

g60wall

Not many people care for the knowledge I have on these cars glad to help, were are you located?

g60wall

I switched from the 19 to 18s made a huge difference in ride quality

cmpcpro

I am very grateful when I find someone who knows about the cars I have! I can't thank you enough! I appreciate those pictures! Do you think those people who stack those rubber grommets inbetween them and the shock mount are helping the problem at all? I am located in So Cal.

g60wall

That guy nick knows his way around our cars impeccably. I do believe it helps as it makes sense. After seeing the shock removed, but if your signing up to keep the abc rolling I would just replace the struts(I know expensive)

cmpcpro

That's true. I know Arnott sells them rebuilt but I didn't think the top mount could be replaced so not sure what they do. May have to go MB oem

cmpcpro

What also confuses me is when I start the car warm after at least ten minutes or so 1/3 of the time I will feel a little thump on the floorboard.. the engine and tranny mounts are a couple months old so they aren't it.. but maybe it's that accumulator..? But it never does it cold.. I really wish I could figure out what that is..

cmpcpro

Well I have an idea why it's riding like this. Checked the display for tire pressure and Keyes Mercedes filled them to 41-38 psi and the factory calls for the 19" to be 32 front and 35 rear! Going to correct it and try again.

cmpcpro

Well I guess the tirepressure.com site was wrong. The sticker on my door jam says 36 front and 42 rear which is where I had it but sure enough they were at 41-38.. I'm hoping a few pounds of pressure was the cause in these 19" wheels but I will find out soon. Still going to check those top strut mounts after I see yours and if they are bad I'll replace them.

amstel78

I don't have issues with bumps like Chris has, but I do have clunks. Turns out there's play in the lower control arm ball joints and thrust arms. I'll have to tackle this at some point in the future. As for only buying MB lower control arms... why? If just going by my car, they've developed slop at less than 56k miles. Doesn't inspire too much confidence in their parts quality.

amstel78

Hey Chris, I'd start with playing with tire pressures first. Only drop by 1 or 2 pounds, and try not to exceed 5 pounds otherwise you'll get uneven tire wear. As for the Michelin Cups - those have very stiff sidewalls. Could just be that as well. I've noticed that even with Comfort mode on in ABC, it's still a fairly firm ride.

cmpcpro

Hey James,

Believe it or not the MB suspension parts are the best. Our cars are designed for smoothness and comfort. That's why we have liquid filled mounts/bushings. 60k miles is absolutely normal for these. They could have ran a stiffer rubber or even a poly but ride would suffer significantly.

I'm going to test drive now that I've corrected PSI, but I have a feeling it's a combination of my pickiness/running 19" wheels and the higher PSI that did it. We'll see!

cmpcpro

Thanks James!

I'm starting to think the same thing! I'm now at the factory 36 front and 42 rear so that's about 3-4lbs down in the front and on 19" wheels I'm hoping that will help a good bit! It wasn't horrible just a little too stiff for what I thought an S should be but with the AMG set up and now your saying those tires are equipped with stiff sidewalls I'm betting it's all these combined.. I'll keep you posted!

amstel78

AMG tunes the hydraulic dampers a bit differently than their non-AMG counterparts. Different valves, rebound rates, etc. So even in comfort mode, it's still a stiff but fairly compliant ride. Compare that with a non-AMG S-class or even E class, and it's like driving a boat. Lots of body roll but the suspension sure is comfy.

Don't forget as well that non-AMG cars have smaller diameter wheels and taller sidewall tires. I think you said you had Michelin Pilot Sport tires? Are they regular PS2 / PS3 tires or are they the Cups? Doesn't matter much, except the cups are a track-ready tire. The regular Pilot Sports are more for the street but still have an extremely stiff sidewall. In conjunction with low sidewall height, you're going to feel more road imperfections.

I wouldn't worry too much about it. Your suspension from what I've read is in fine working order. Worry less, drive more.

MooksM275

Check your rear subframe bushings. The front bushings on the rear subframe are susceptible to aging and moving about. Once this happens, the rear subframe is moving and banging while the abc system tries to compensate and the ride gets very harsh. The rear subframe bushings can be inspected easily using a leverage bar to inspect for excess movement up and down etc. An easily overlooked item and can affect the whole cars ride feel.

cmpcpro

Thanks again James!!

cmpcpro

Thanks! It's going in this morning for the new starter and I am going to have him check under the drivers side floor board too as once in a while when starting I hear and feel something tapping the floor. I also feel a very slight vibration in the floor at just a certain RPM just when it's cold so I'm thinking either an ABC Line or the exhaust maybe. I was thinking about subframe bushings as sometimes I can hit a bump and feel the car so side to side a slight bit (I am super sensitive and can pick apart a brand new cars flaws too so for the average person my car probably feels like new) but I haven't had a chance to research them yet.. I was going to check if there are any body mounts or something similar in the front that can go out.

Thanks again!

cmpcpro

Well ABC lines under the floor are all fine and secure and the rear subframe mounts and arms are all perfect with no cracking and no play with crowbar more than normal! Car does ride a lot better with the lowered air pressure though. Oh and that new starter? That had to have been the issue because now the car turns over so super fast!

MooksM275

When you say the subframe bushings don't have play "more than normal", what do you mean? These subframes can wear in a way that allows excess movement up and down rather than merely left to right. If it is very easy to move the subframe bushing up and down when the wheels are subspended then this is not normal. This movement up and down will happen when the car is hitting bumps and will not be under the normal control of the abc system. This will create a feeling of rough ride.

Best

cmpcpro

Thanks what I meant was he checked them and they had no cracks, then he checked them with a crowbar and other then the minor flex you would expect from a bushing they were tight. He owns the best Mercedes specialist shop around so I'm pretty confident he checked them correctly. Thank you for the info though! I love to learn as much as possible.