I have a set of Kumho SPT with 24,000 miles on them. They still perform
great and have plenty of tread left but they have gotten extremely noisy.
I usually run 32 psi all around. Is this normal for this particular tire or are
they going south. Any thoughts, thanks.

 

How often have you rotated them? If you haven't that is why you have your noise. At 24,000 rotating may or may not help.

 

when i had my set i rotated them every 5000km, and never had any noise problems

 

I do rotate them every 5 - 7 thousand miles. I think that I might just let
Santa bring me a set of Goodyear F-1's.

 

Yes, tell Santa to put on his summer clothes and drop by soon.

How old are the tires? If you have put the miles on over about 2 years or longer then as the rubber ages it gets hard and noise increases.

Tires don't last forever and they are best when new. Handling and road comfort is reduced over time for any tire.

Goodyear F1 GS-D3s are considerably better for handling and for comfort than Kumho SPT but they do cost more.

 

You are doing the right thing. Guess we can cross wear issues of the causes list. You could have a broken or shifted belt in a tire. If you rotate the tires does the sound change or move?

 

The tires are 18 months old. The road noise comes mainly from the rear,
but I'm going to rotate them next week so I'll see if it sounds the same or
moves to the front. Thanks.

 

Crashton, I see in your gallery you were at Mid-Ohio for the Rolex. I spent
some time in the paddock for the #197 and 198 cars. Got to talk to Frank
(car builder and head wrench). I learned a lot about both cars and enjoyed
his sharing of info.

 

the GS-D3's are pretty noisy too when they start to wear.
not as noisy as S03's, but still pretty loud if it bothers you.

if you drive around town with the window down like me it
really doesn't matter that much, but for those audiophile
types, GS-D3's are probably still too noisy.

 

Check the wear on the inside of the rear tires. Maybe your alignment is off (Toe settings) and that caused the tire to wear funny and start making noise. Happened to me once....