Retxpres

Just drove my 1994 Corvette home from my Florida condo. 1330 mile trip.
Car did a lot of sitting in the garage and got limited use. Always experienced flat spots when I took her out for the first few miles.
Car ran fine, steering solid at high speed. Goodyear Eagle F1 tires about six years old. 5,000 miles tops on them.
I wanted to fresh up the car when I got her home, so I ordered a set of ZR1 wheels with the GS offset from a forum sponsor. Wheels came in and had them mounted by a small tire shop here on Long Island. Got the car back and the whole car shook at 65+ mph. Brought the car back and they said they rebalanced the wheels but they just could not get it right. They recommended that I take the car to Mavis, a large tire center that just opened and had new equipment.
Took the car to Mavis they found...
LF perfect
RF 1 oz off
LB 1oz off
RB 2.5 oz off

Get the car back, car rides better but still not right.
When I drove this car previously, the faster it went the more it felt that it sucked down. Now it feels like the front end is lifting. Front end feel lite. Not a good grip of the road.
Could these tires gone bad. In Florida these tires were great. Smooth roads. Warm temps. Roads here on Long Island are not as smooth. Temperature has not been warm, 50's at best. These tires always sucked in cold temps. They ride hard in cold weather.
Personally I think the tires even though they look brand new, need to be replaced. I do not think it is the wheels. Possible switching from Sawblades to new wheels they are just not matching...
Any thoughts on this???

WVZR-1

The tires are date coded so there's no reason to be guessing at age. You didn't mention the type of wheel balance you had done. Do you know?

You mention buying wheels and you mention GS offsets. Did you buy 9.5 X 4 or 2 X 9.5 and 2 X 11.0? Did you try stretching your 285's to the 11's and your 255's to the 9.5's? There's much you haven't shared.

Could the tires be old you asked. Yes, that would be a first guess and the extended periods of sitting didn't help either.

Klondike

It's possible they don't 'round out' in the cold temps, but I'd think they might not be round any more from the long sitting they have done. Jack up one side and put some object like a block of wood close to the tread. Spin the tire and watch if the tread moves closer then farther away as the wheel turns. This is "run-out", or out of round. You can balance an egg, but it still wont roll worth a damn! You could have the tires shaved or trued, but it may be a wasted expense on tires that are old in years. It's a shame to have to toss such low mile tires, but the rubber gets old on them regardless of the miles and they can become dangerously slick and can delaminate and fly apart without warning.

Retxpres

If I am reading this right the tires were manufactured on the 38 week of 2002. See attached photo. That would make these tires 12 years old even though I have had them on this car for roughly 6 years. Could this be right?

The rims are 9 1/2" front 11" rear.

I have 285's to the 11's and your 255's to the 9.5's. This is the same size rims as the Sawblades that were the original rims.

Today I took I nice ride in the car. Probably about 80 miles. First real ride since they have been mounted on the new rims. Temperature was 70 degrees. Seams like they are riding better than they were.

Kmcoldcars

That tire was definitely made in the 38th week of 2002. If they are all the same year them it is past time to get some good tires. They will be softer, ride better, be quieter, have better traction and be much safer than what is on the car now.

astepup

I do believe if I'm not mistaken, that original sawblades on a 94 are 8.5x17 inches in front and 9.5x17 in the rear. At least that's what my sawblades measured out to be. I read a post some time ago about inflating the tires to 40 psi if it's going to sit awhile to avoid flat spots. I've been doing that for a few winters now and have had no problems.

astepup said that

RollaMo-LT4

You really shouldn't be running that 285/40-17 tire on an 11" wide rim.

Your factory rear rim running that tire was a 9.5" rim.
The factory 11" rims that the GS came with had a 315/35-17 rear tire.

You've also put your factory 255/45-17 tire onto a 9.5" rim where the factory used a 8.5" rim for that size tire.

Since your tires are really much older than you should be running at this time anyway, now is a good time to purchase the correct size tires for your new rims.

I would go with the following, as they are the factory sizes for your new rims.
Front: 275/40-17
Rear: 315/35-17

Retxpres

Ok, now it is all starting to make sence...
I have 12 year old tires mounted on rims that are 1" wider on the front and 1 1/2"s wider in the back. You think out of the two places that I took my car to, they would have told me that I was running 12 year old tires. These are tire guys?

If I were to order new tires I would go with the Nitto 555's. With the sizes mention above, would I have any clearence issues?
I do not want to solve one problem and have another.

Thanks guys... I have been going crazy to figure out what is going on.

Kmcoldcars

Yes, the tire guys should have told you your tires were twelve years old. However, you should have already known that. With all the threads on tires and their age with the date codes on the tires EVERYONE should know the age of their tires. It is the owners responsibility.

Retxpres

I agree... Will not happen to me again