Today i found out that some C5 have problems with the Harmonic Balancer so I went out and started my car and look at the Harmonic balancer wile it was running the thing look like it was going to come apart .:ack2: so mine is bad my car has only 39000 miles on it they say that it can come apart and damage the engine cover and oil pan so I will replace with a high performance underdrive balancer .just whanted to pass it on so that other pepole will know about this before they damge there car.