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First Vette, shaking problem.
Thread Starter
3rd Gear
Joined: Sep 2012
Posts: 3
Likes: 0
From: Frisco TX
First Vette, shaking problem.
I bought my first Corvette last month, an 85 C4. It has 132k original miles, and had been sitting under a tarp in a Carport for the last 1.5 years. Previous owner passed away. Car started right up, and runs great, no smoke, everything works.
The one problem, the tires have less than 800 miles on them, but from 53 to 61 MPH, the shakes like the space shuttle on launch!
The tire shop said everything balances out, but they did mention there were flat spots and asked if the car had been sitting.
So, my question...anyone else have this issue ever? Tie rods look and feel fine, and there is no shake at any other speeds...
Whats y'alls advice?
I'm hooked now, and told my wife not to give me any trouble about it!
I now have a goal of getting a C1,2,3,5,and a C6. (C7 will have to wait until after it's been out for a couple years after it's released in the spring!) I can't believe I waited this long for a Vette.
The one problem, the tires have less than 800 miles on them, but from 53 to 61 MPH, the shakes like the space shuttle on launch!
The tire shop said everything balances out, but they did mention there were flat spots and asked if the car had been sitting.
So, my question...anyone else have this issue ever? Tie rods look and feel fine, and there is no shake at any other speeds...
Whats y'alls advice?
I'm hooked now, and told my wife not to give me any trouble about it!
I now have a goal of getting a C1,2,3,5,and a C6. (C7 will have to wait until after it's been out for a couple years after it's released in the spring!) I can't believe I waited this long for a Vette.
Melting Slicks
Joined: Mar 2008
Posts: 2,351
Likes: 222
From: Delta B.C. Canada
2023 C7 of the Year Finalist - Unmodified
2019 C4 of Year Finalist (appearance mods)
2015 C4 of Year Finalist
Flat spots are a definite possibility. That's why you should over-inflate them while storing a car.
If you inflate to 32-35#, and drive it easy for a while, they should go back to round. The higher inflation pressure will give a lot less traction in the curves, so be restrained.
If they still shake after a couple hundred miles of driving, you may have to replace them. Have you checked the date codes? If they are more than 6 years old, they should be replaced anyway.
If you inflate to 32-35#, and drive it easy for a while, they should go back to round. The higher inflation pressure will give a lot less traction in the curves, so be restrained.
If they still shake after a couple hundred miles of driving, you may have to replace them. Have you checked the date codes? If they are more than 6 years old, they should be replaced anyway.
Racer
Joined: May 2008
Posts: 378
Likes: 0
From: Asheville North Carolina
Also check the u joints in the half shafts and the wheel bearings. Both of these were gone on my car. I replaced the u joints on both sides first and that took care of most of the problem. With a small vibration left at those exact speeds you describe I replaced my hub bearing assemblies.
Drives like new!
Drives like new!
Safety Car
Joined: Aug 2009
Posts: 3,752
Likes: 276
From: Melbourne, Victoria, Australia
Race Director
Joined: Nov 2003
Posts: 12,221
Likes: 446
From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
C4 of Year Winner (appearance mods) 2019
Try the overinlation first.
There are two types of balancing....spin balancing and road force balancing. Spin balancing has a problem identifying the type of issue you have. Road force is specifically designed to identify issues where out-of-round, out-of-balance tires are "pounding" the pavement (because they're not perfect.
Sometimes, they can correct/improve imperfect tires thru a combination of weights and reposition/remouning. If not, they can identify when tires will never be perfect/enjoyable.
I used road force to identify that Sumitomos were a POS. I had 2 of 4 tires that had a 36lb imbalance. And, they were new (ie. no flat spots).
Sitting 1.5 yrs is enough to get flat spots...and if its visible, you may not get that to "go away".
Most vette tires can be signifficantly overinflated. I'd probably try them in the high 30's or even 40's for a couple hundred (hwy) miles. Probably more likely to "come out" on a hot summer day.
There are two types of balancing....spin balancing and road force balancing. Spin balancing has a problem identifying the type of issue you have. Road force is specifically designed to identify issues where out-of-round, out-of-balance tires are "pounding" the pavement (because they're not perfect.
Sometimes, they can correct/improve imperfect tires thru a combination of weights and reposition/remouning. If not, they can identify when tires will never be perfect/enjoyable.
I used road force to identify that Sumitomos were a POS. I had 2 of 4 tires that had a 36lb imbalance. And, they were new (ie. no flat spots).
Sitting 1.5 yrs is enough to get flat spots...and if its visible, you may not get that to "go away".
Most vette tires can be signifficantly overinflated. I'd probably try them in the high 30's or even 40's for a couple hundred (hwy) miles. Probably more likely to "come out" on a hot summer day.
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Max G’s
Joined: Nov 2008
Posts: 2,751
Likes: 79
From: Monroe OH
NCM Sinkhole Donor
If tires were flat spotted, the car would vibrate at all speeds. It is either tires are out of balance or you have a bad rim(wheel). Another possibility would be shocks, but not that likely if only shakes between 53 and 61. Go to another tire installer and have them align and balance the tires and ask if they can check the wheels for out of round.