feeshta

Hello all. I've been searching on this for a while now, and I'm a bit at a loss as to how to find the correct part numbers to order for a couple items I need to replace after switching to coilovers this past weekend. The rear suspension on the wagons is a complete SOB by the way. That job sucked ***.

So, When you switch to the E350 control arms in order to install a coil spring in place of the old air springs, there is a bit of a difference that is workable, but not ideal. The issue is that the control arms on the Airmatic models are cast aluminum, and the replacements are stamped steel. The stamped steel is very thin where the mounting bolts go through for the inner mounting point, and particularly the mounting point for the dampers. This means that if you reuse the original hardware, you have like an inch and a half of extra bolt sticking out the side of your control arm. It's not in the way of anything except possibly the plastic covers fitting. I'm not sure because I don't have those yet, but it just does not look right in any way shape or form and offers a possible snag point for road debris I would prefer to avoid.

I've been looking for the part numbers for the bolts that would go in these two spots on the E350, but so far have not been able to find them. Parts diagrams I have found seem to show the same hardware with both control arm options, but this is obviously incorrect. Went to the dealership to see if they could help, but nobody there spoke English, and we were not able to find a solution through the language barrier. Can anyone offer some guidance?

Plutoe

look here Mercedes-Benz Electronic Spare Parts Catalogue Online

E55Greasemonkey

I just looked at the latest version of MB's online catalog, and sure enough it shows the same bolts for the aluminum or steel lower arms. The picture does show both different arms also in the same picture. Time to look under an E350 and see if the bolt sticks out as far as what you're seeing. The other option is to cut the bolts down and run a die over the threads. (screw the die on the bolt before cutting)

feeshta

Thanks Greasemonkey. At least I know I'm not nuts now. I had thought about cutting the existing bolts down, but figured it would be better to get properly fitting ones if possible. I wouldn't have thought of putting the die onto the threads before cutting, but that does make a lot of sense. I probably would have cut the part that sticks out off while they are on the car to be honest.

One interesting thought I had was that if you reverse the direction of the inner bolt, you could save yourself a ton of problems in the future. Unfortunately that isn't possible with the current bolt length, as they stick out too far and interfere with the movement of the rearward control arm if you put them through backwards from the factory installation direction. I'm wondering if it might be possible if you cut the bolts down slightly.

The reason you might want to do this is to avoid having to drop the rear portion of the exhaust in order to get that bolt out. The bolt has to come out in order to adjust ride height, but to get it out you have to unbolt the rearward control arms and undo 4 exhaust hangers in order to get clearance to pull the bolts all of the way out. If you could simply reverse the direction of the bolts, it would save about an hours worth of time and effort when you want to adjust ride height, which I have to do again this weekend. The ride height settled a bit over the first couple days driving the car, and now it scrapes over ramp transitions in the parking garage at work.

E55Greasemonkey

I will get a picture of the E350 rear suspension next time I see one, but I am on vacation for 1 week. My E350 wagon won't help as it has rear air only.