I have a 2001 cl55 amg, it has started to make a funny knocking noise over bumps which seems to be coming from the rear passenger side shock... I have had a look and there seems to be alot of thick oily gunk around the spring and in the arch, there is none of this in any other arch. I have been looking at the abc fluid level on the dipstick in the engine and it doesn't appear to have changed in over a week or 2. No warning lights of anything have come up. Any of you guys have any idea what my problem could be?!