Blackbradpitt

So I recently installed all new 06 sport springs on my 02 C320. Not too hard putting in. Thanks to help from people here. Got about an 1.5" drop and the ride is so much better. At least for a while. After installing the rears, I noticed a pretty loud rattling noise coming from the back. It sound like I left something hard the trunk and its bouncing around over every bump. But I know it's because of the springs, and there is nothing in the trunk. I thought the first time I just didnt put the rear springs all the way in correctly. So I redid them and the sound went away. Perfect, for abou 7-10 days, then the rattle noise came back. Once again, I removed the springs, and put them back on, making sure it was lined up with the groove at the top and bolts were nice and tight. Worked fine, until another week passed and I was back in the same place. As good as I've become at doing them, it's 100 degrees out here and before I sweat my *** off again reinstalling them, I was hoping someone might have an idea of what I'm doing wrong or anything really. I'm stumped at this point. I'd record it but my exhaust will probably just drown out the rattle. It's not extremely loud, but noticeable when driving over any rough of road that isnt perfectly smooth, even at low mph. Any ideas or advice would be greatly appreciated.

phister

Did you replace the shocks as well? If not your rears might be bottoming out. Also it could be the exhaust knocking.

Blackbradpitt

No it's not the exhaust. That was actually my first thought, but I've checked and it's fine. Also like I said if i re-do the springs, everything is fine for a few days. I did not change the rear shocks. Sorry I dont know much about those. But would they not be bottoming out all the time? Even right after putting the springs back in. Thanks for the suggestions.

phister

Sometimes it takes awhile to get the suspension settled so it might not occur till a couple days. It could also be the sway bar endlinks or bushings. Mine got loose and made a knocking noise upfront. Tightened it all down and it went away.

Boom vang

Can one replace the springs in a standard model with the sport version to a standard without changing the shocks and struts? I know that the sway bars are different

mtnman82

Sorry I missed this - did you evrer get it figured out? I wonder if there's a right/left spring, or if the tops of the spring seats are rotated, allowing the spring to rotate? Sounds like the spring is roating out of the grooves in the seats? Can you measure and see if the car is slightly lower (i.e. settled) after a reset and a few days of driving? I'm doubting it's the shock, as I would think you'd just be using less travel...

Wilburnter

Tightened it all down and it went away

Blackbradpitt

No still havent figured it out. But I was thinking the same thing. One thing I did not do when changing the rear springs is change the pads. Or shims I think their also called, right? Is that a must change thing? And do all mercedes basically use the same type spring pad and it's just differences in the thickness of them. Cause I swear I can't find one specific to my car, and they seem a lil hard to find.

Also, im sure this sounds stupid. But do I now need a rear camber kit? I've read ghostriders camber kit thread, and it sounds like it's something im supposed to have, but honestly I still dont even understand what it is or does. I probably should have known this stuff "before" changing my springs. Maybe got a lil ahead of myself.

Blackbradpitt

Was also gonna try and take it apart again tonight if I had time. Would any specific pics of some part help?

phister

W203 have 4 different thickness in spring pads for the rear. Go to rmeuropean and buy some, only like 15 or less.

mtnman82

When I put in the H&R sport springs, the rear sagged initially and so I put in thicker pads to level the car out. Not sure if they're required or not... If the pads in there now don't keep the spring in tight at all times - i.e. if they are a tad loose when the suspension travel is extended all the way - I could see them rotating as you describe. Not sure if that's what's going on or not, just a thought.

Yes on the camber kit. I didn't think I needed the it when I first installed the lower springs. I liked the way the car handled with the negative camber and the tires didn't seem to be wearing that uneven... Until after several short months I noticed the inside of the rears were bald and I had plenty of tread left on the outside. Ghostrider's kit was a breeze to install and if I remember correctly I have ~0.5 degree negative camber dialed in presently.