white99c2

So I was told at Disount tire today. The re-balanced them and it's worse than when I brought it there. The tires are Kumho Escta SPT's with maybe 3000 miles on them and they make so much noise I can hear every RPM. Kumho said no warranty because the cupping is on the inside of all 4 tires. Can I do anything to fix these tires?

SSST

I don't think there is any way to fix the tires, but you need to find what is causing the cupping and fix that before you buy new tires.

Speedyellow993

Can they be shaved? Just a thought....

I've always had issues with my Kuhmos.

GL

Macster

The car's alignment is probably off. Even so, even if you have the car aligned the worn tires can affect the outcome of the alignment and it may not be as good as it would be with new tires on the car at the time of the alignment.

Up to you if you want to throw an alignment at the vehicle and see if this quiets the tires.

Be aware even if the alignment helps, the tires due to their wear may still be noisy until they lose the wear pattern arising from the previous alignment.

'course tire life will be shortened.

You might be better off simply replacing the tires now and then with new tires installed having the alignment done.

Generally the guidelines for alignment are the gas tank should be full; the car empty of dead weight (junk that sometimes collects in the car -- both of my cars are carrying 12 quarts of motor oil -- both cars are due for an oil/filter service soon -- among other stuff) -- and the spare tire, tool kit should be present and properly secured.

Sincerely,

Macster.

nick49

Providing your alignment is spot on cupping is caused from too low of air pressure. The contact patch is distorted in an underinflated tire and that's how the tire wears. The noise is from the scalloped wear or high and low areas similar to a knobby motorcycle tire. Running the tires at the proper pressures or maybe even 5-10% higher for a while will eventually even out the wear as the high points wear down to math the low ones. The noise should slowly get better the more you drive.

fpb111

Swap the tires on the rims to get the outside "smoother" edge inside, then run them another 3k and get new ones. What tire pressures were/are you using? What did the tires look like 4k ago? (before you mounted the Kumho Escta SPT's?)

white99c2

Here's the scoop. The old tires came off in December and wore perfectly even. My alignment is right on, these tires a crap. They are so flippin loud I can't even hear the engine and have symptoms of flat spots. I'm a fanatic about the air pressure basically a fanatic about everything with this flippin car so I feel I got railroaded by Kumho, never again. Here goes another $1000.

white99c2

When Diccount tire measured my tires the rears have 7/32nds left and the fronts have 8/32nds left. The guy told me they come new with 9/32nds.
I have maybe 3000 miles on these tires and they are toast, I'm disgusted.

Barn996

Once they are cupped you are cooked. I had cupped Michelins and they became so noisy they had to be replaced.

Speedyellow993

We hate to waste but maybe it's time to bite the bullet and change them. It seems like the tires are taking away from the pleasure of driving. Im a big fan of Mich PS. They are expensive, sticky, super quite and don't last too long which is not an issue for me due to my low milage driving.

GL

SSST

I am currently running the Hankooks with about 3k miles and had been very pleased with them. I had PS2s, but a tire went bad on me while traveling and the Hankooks were the best I could get on short notice.

At half the price of the PS2, it is 90% as good. Very quiet and wet weather grip is excellent. They feel a little vague when cornering near the limit, but the grip has never been an issue.

Excellent tire for the money.

No HTwo O

White99c2, I have the same tires on my Turbo. They have been great over the past +20,000 miles (1 set of fronts and 2 sets or rears).

What tire pressures have you been running?

white99c2

I work for a dealer so today I went in a luckily sold a really nice 2011 Corvette Grand Sport Convertible on my day off and used the nitrogen machine that dumps the air from the tires fills them dumps it again and fills them again. I set it on 38 all the way around and took the car for a nice hell ride through a really windy stretch of road. With the tire pressure up the noise is still there but not as pronounced as it was and the car rides a bit harder but no big deal about that.
The tires are really new, I bought the wheels and tires from another party with about a 1000 miles on them and obviously he had a problem with his car because these tires have been loud from day one making a thump thump thump sound at every RPM. Stupid me thought they were a bit flat spotted and driving on them would fix them. I'm hoping that running the pressure a bit high with nitrogen instead of air on my perfectly aligned car with wear them back in flat or close to it, we shall see. The noise is ugly.

No HTwo O

Congrats on your salesmenship!

Nitrogen won't do a thing (that regular air won't do with regards to your current situation).

38 PSI sounds kind of high for the fronts and slightly low for the rears. You really need to set the tire pressures properly, and with an accurate gauge.

I'd suggest 36 front and 40 rear for starters. But I don't know OEM spec for the 996.

Scarab440

Sounds like you may of had a bit of bad luck with the tires since they were used and may not have been exactly as advertised.

the Khumo XS's may be a better match for your car. they are a but softer and more aggressive than the SPT's. I've run a set of XS's for the last 5K miles and they have been perfect.

also, if they are cupped they are toast... nearly new or not.. its just a matter of how long you can live with them and if they pose a safety hazard or not.