C3 bouncing vibration
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Joined: May 2025
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C3 bouncing vibration
Hi everyone,
I have a 1979 Corvette and the other week I drove it for like two hours. About an hour and a half in, I noticed the car seemed to be bouncing and some vibration almost shaking. I’m not sure what could be causing this or what needs to be replaced. It drove fine for the first hour or so.
I have a 1979 Corvette and the other week I drove it for like two hours. About an hour and a half in, I noticed the car seemed to be bouncing and some vibration almost shaking. I’m not sure what could be causing this or what needs to be replaced. It drove fine for the first hour or so.
Le Mans Master
Joined: Jan 2007
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From: Omaha NE
2025 c3 ('74-'82) of the Year Finalist - Unmodified
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How old are your tires? Coming out of nowhere I'd check them first...
Melting Slicks
Joined: Jul 2006
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From: Salmon Arm, BC
It could be the tires, worn out shocks, driveshaft imbalance, or driveshaft angles. Another thing to consider, it could have been the road conditions as well. Several times I’ve noticed something weird and once on smoother road the condition disappears….
Check the condition of the transmission mount at the crossmember, and the bushings under the rearend.
Check the condition of the transmission mount at the crossmember, and the bushings under the rearend.
Is my vette stock?? HAHA
Joined: Oct 2015
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From: Im not allowed to tell you
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first check oyur tires for bulging or seperation of the treads. Push up and down on the rear of the car about 3-5 times then let go, If it bounces more than once after you let go you might have blown a shock, same with the front.
Start there, its the easiest things to check and most likely for your symptoms. if it isnt one of those then start looking for a loose drive shaft or half shaft, would be a bad u joint but those usually clunk when they go bad. The drive shaft would be a faster vibration than the wheels are turning.
IF its a slow wobble then it would be related to the half shafts or tires/ shocks.
If it was a higher vibration than the tires are spinning, then it could be a driveshaft. If its the motor then the vibration would change with the engine rpm and could be checked in different gears as the vibration would change
Start there, its the easiest things to check and most likely for your symptoms. if it isnt one of those then start looking for a loose drive shaft or half shaft, would be a bad u joint but those usually clunk when they go bad. The drive shaft would be a faster vibration than the wheels are turning.
IF its a slow wobble then it would be related to the half shafts or tires/ shocks.
If it was a higher vibration than the tires are spinning, then it could be a driveshaft. If its the motor then the vibration would change with the engine rpm and could be checked in different gears as the vibration would change
Drifting
Joined: Jun 2025
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As others have indicated; TIRES, belts delamination, tread separation. If they're more than 5 or 6 years old, they're suspect. You can damage a tire by pothole etc, and it may take weeks for it to separate. Suggest interpret each tire's date code (on sidewall). Jack car up and And closely inspect each tire all over and while tire rotates (Lumps/Bulge). If-when a tire comes apart on a fiberglass car, that'll leave a mark.
