Suspension Issue - need opinions.
Thread Starter
Safety Car
Joined: Jan 2000
Posts: 3,905
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From: Orlando FL
Suspension Issue - need opinions.
I have had a thumping in the left front suspension for a couple weeks now. My car is a 2000 6M Z51 Coupe with around 68K miles. Suspension is stock with the exception of Koni adjustable shocks. Not sure of exactly which model as they were on the car when I bought it. The "thump" occurs whenever there is a load on the left front. It is much louder when the when the left side loads alone (such as a pot hole or manhole cover) than when both front hit at the same time. The thump occurs at at max travel, and no other time. There is no other indication that anything is wrong while driving, no vibrations, no shake, no nothing. Car drives and performs as it always has. I was thinking it was a shock issue, or possibly the sway bar. I pulled the left front tire and inspected the shock. No evidence of leaks, only issue is there is a large rubber bumper that free floats on the shock shaft, that is deteriorating, the rubber seems to be breaking down. The right side appears what I would think normal for a rubber suspension piece. Could the deteriorating stop cause the thump? Is there anything I am missing?
Thanks!
Thanks!
Safety Car
Joined: May 2006
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From: Northern Virginia
St. Jude Donor '08
Based on what you posted it sounds like your suspension is bottoming out (no more travel left). Most suspension have bumper stops on the shocks. Is your car lowered or have the stops been cut?
Hope that helps.
Hope that helps.
Tech Contributor
Joined: Dec 1999
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
I would suspect that the shock is toast and can NO LONGER dampen properly. Remove the shock and see if it has the correct dampening in compression as well as rebound. Just pressing on the fender is NOT going to tell you that you have a shock problem as the C5 suspension is very stiff and will hide a shock issue.
The shock is most likely contacting the top limit of the shock. Is your car lowered?? If so how much. It may be too much for the shocks that you have on there now.
Bill
The shock is most likely contacting the top limit of the shock. Is your car lowered?? If so how much. It may be too much for the shocks that you have on there now.
Bill
Thread Starter
Safety Car
Joined: Jan 2000
Posts: 3,905
Likes: 250
From: Orlando FL
I was thinking that maybe the shock was toast. The car is lowered slightly, but not all of the way down. The shocks have been on it the 3 years I have owned the car. I will pull the shock this weekend and check it out.
