I have a vibration that becomes noticeable over 70 MPH on my 08 Vert.
This started when I had new PD2 AS Michelin tires installed at Discount Tire.
I went back much later, thinking the tires may need to break in.
I went back to DT the checked the balance, and found one wheel bent.
I had a new wheel installed today, to replace the bent one.
Same vibration, does anyone have a suggestion as to how to go about locating the problem?
I may find a small tire dealer, so I can be there to check each wheel myself.
DT frowns on people in their bays, not to mention they are so busy they don’t have time to let me check each wheel as I would like to.

 

Have all four wheels pulled and re-balanced. Unless there's an obviously blown shock absorber, I've yet to come across a vibration that starts over 70 that wasn't a bent or unbalanced wheel/tire. Wheel bearings can also cause vibes, but they don't wait to 70 to be felt. The fact that you had one bent rim suggests it may have a companion.

 

I think you're right, that's it's most likely another wheel.
I have a dial indicator, so I need to find a shop that will let me put each wheel on the ballancer and check them myself.
I did have the balance rechecked already.
That;s when they found the bent wheel.
I do have the "Service Ride Control" come on every once in a while. But usually after driving a while, when I restart, it goes away.

 

This may sound crazy but have you looked close at all four tires? I had a set of Michelins installed at a Town Fair Tire and found after close inspection that they had installed a NON run flat on the left front. All four tires MUST match!!

 

It only takes a few thousands run out on their machine before they tell you the wheel is bent. I had two that were just out of their tolerance on my 04. I watched them spin them. Not much run out. I had them road force balanced. There was still a little vibration at 80. I had them road force balanced and all was well. This is the way to do high speed tires IMHO. Later! Frank

 

Didn't have to put anything on this wheel.
They told me it was bent/warped, and I looked at it on the balancer.
I could see it wooble.
Matter of fact I can't believe I couldn't/can't feel it at lower speeds.

I will check to be sure all tires are the same.

Not to change the subject, but I cringe every time I have to have someone else work on my car.
Just like having the wheel installed at DT this morning.
The guy pulled it out, and was sitting in it pushing buttons.
So I went out, and he told me it was ready to go, but he knew the tpms was working but couldn’t get it to set like it should. I told him to get the instructions, and it will work., He did and it did.
I went thru this when they put the tires on. Four different guys took turns getting my car, and each one pushed every button they could find. Finally one decided to get the instructions, and it took less than one minute.
A few minutes ago I went to one of those Quick oil change places (It was the last time). I just needed to get it changed today. When they finished two guys did the same thing, taking turns getting in and pushing buttons. I came out, and one told me I had to leave the service area. I told him he could kiss my A$$. It’s my car, and I want to see what they were doing. My first thought was there wasn’t any oil pressure. But all it was, them trying to reset the oil life. They were even pushing the HUD buttons.
I told them how to set it, and also told them it’s not really rocket science, especially when he had already gone back in the office, and printed out how to reset it on a 08 Corvette.
Sorry, I just had to vet a little.

 

If the vehicle is OK mechanically, try a road force balance. Find a shop with a Hunter 9700.

 

all good suggestions above. you didn't say if it was front or rear, but sometimes when a wheel is bent, say RF, the RR will also get it. also, you don't say if you started w. original or repro wheels and what was put on, repro or originals. sometimes, a mix of wheels doesn't work out well.

still, I'd go first for the road force balance (Hunter 9500,9600, etc.).

 

I will find someone with the Hunter road force balance 9700.
The wheel I relaced was the right rear.
The wheel apeared to be warped (like from mounting) rather than it hit something.
They are factory Gumby chrome wheels.
How-ever I did replace it with a replica.
The copy wheel looked good (I know that doesn't matter), an even though I didn't weigh them, they seem to be close to the same weight.
This give me a few things to try.
Thanks

 

if it's a factory gumby you replaced, there is a potential issue: the factory wheels is forged. the replica most likely is not. I don't know if that, alone, can constitute a problem, but I will say there have been several/many who have said their repro wheels do not balance and/or have runout/non-true issues. whatever wheel you put on, that's where I'd look first.

as to finding a Hunter dealer, http://www.gsp9700.com/. you'lll get a site where you can plug in your zip and it'll list out all stores in your area.

 

They didn't have any problem with getting it o balance, when they mounted it. When I find the company that has the Hunter, we will recheck the balance, and hopefully find the problem.

 

id have to say its either another bent rim (thats my vote) or tire outta balance. but if they rebalanced them they should be ok.

 

good luck and come back and tell us what the issue was as a follow up!

 

I would go back to DT and talk to the manager, you bought the tires there they should have found the bent wheel(s) when they balanced them. I'll bet they will help, service is there stock and trade, good luck.

 

I did go back to DT, and I did call them the following day after putting the Michelins on, and told them about the vibration.
As usual they offered for me to bring it in, and they would check the balance.
As things were, and with my procrastination 6 months before I made it back in.
So I didn’t push the issue, since it was my fault not going back right away.
I even remember one of the guys having a lot of trouble taking the old tires off, and eventually having to get help.
Didn't think anything of it then, but I believe this was when the rim was warped. He was prying on it pretty hard, with a 3 foot bar.

 

Try remounting the wheels yourself. I had some vibration at 70+ and took the wheels off and remounted them torquing them properly and the vibration went away. Vette wheels are lug centric so if they get lazy mounting them a perfectly balanced wheels can vibrate pretty bad.

 

I had vibration starting at about 50MPH after I had new Michelins put on. Took it back and they drive to another store about a mile a way that had a Hunter High Speed balancer, problem solved.

 

Well I had my tires balanced on the Hunter GSP-9700 today.
The good news I watched him balance each one, and he said all the wheels were within specs,
Which means none were bent or warked.
However, went for a road test, now the vibration is 10 times as bad.
Before it was a mild vibration, that only I could feel.
Now the whole car vibrates at 80-MPH.
So I will go back tomorrow, and let you know what happens.
I'm thinking a weight must have fallen off.
Because he had one fall off while balancing one of the wheels.
Also now the steering wheel shakes, and before it was only in the rear.

 

Some replacement wheels do not have a relief (space) around the hole for the wheel stud for clearance for the tin "nuts" that hold the brake rotors on during factory assembly. OEM wheels have a space for this “nut.” The replacement wheel is then not flat against the face of the brake rotor when installed -- UNLESS the "nut" is removed. The "nut" is not needed once the wheels are installed. Check to see if this is your issue.

 

They re-re-balanced the wheels again today.
I did look the aftermarket wheel also had the relief for the tin nuts.
I'm back to the way it was before the first Road force balance.
I ask if his machine had been calibrated. He said they calibrate them every week.
But every tire/wheel was out of balance.
He even had to bust the tire loose, and rotate it on the wheel.
I don't see any reason to just keep going back, doing the same thing over and over.
I'm going to just bite the bullet, and live with it for a while.
Like I said I think if anyone was in the car with me, they would never notice the vibration.
It may just be the tread on the Michelin Pilot Sport AS/ZP tires.
If noting else, I'm going to find someone that I think really knows what they are doing with the Hunter 9700 balancer.