I have about 15,000 miles on my BFG KDW 2 tires and they are cupping pretty badly. Could this be the result of putting the 255 tires on the 8.5" rim? Both sides are cupping on the inner edge, and since the tires are directional I can only rotate them front to back (have been every 7500 miles). Tire pressure is 32psi.

When I purchased the car new, the dealer installed the BFG KDW 2 tires and I am not impressed with them. They are LOUD! Now this cupping issue. Since I just rotated the tires yesterday I now have a steering wheel shimmy, I'm sure because of the cupping.

 

It sounds like the front end need an alignment. Bad

 

My guess is the dealer had trouble mounting and balancing the larger tire.
It might be because of the narrower rim or the dealer isn't good at balancing in general.
Bad alignment usually results in bad wear in a steady place (e.g. inner or outer).

 

ditto - sounds like alignment to me man

(I had alignment issues with my previous set of tires and the Falkens wore BIG time on the inner edge on the front tires...)

These BFGs ARE loud - but otherwise they grip in both wet and dry and have lived up to my expectations.

 

Cupped in the front or rear before the rotation, and how often have you kept the tires rotated?

<--edit-->
lol, 4 hours of sleep FTW

 

Well I finally had an alignment done. Tire shop says it was barely out of alignment...not nearly enough to cause cupping like I have. He is going to contact BFG to see if they will do anything as far as a warranty credit...we'll see.

I'm happy to hear the car is in alignment...I argued with the tire shop guy in the parking lot that all 4 tires have cupped regardless of front or back. He insisted the car was out of alignment and "impossible" to wear like they have been! Ha!

Now if I do get tires do I stick with the 255's? And what tire? I see tirerack.com has BFG KDWS for $95 in the 235 size...that's tempting going back to OEM considering the problems I've had.

I have 16,000 miles on these tires.

 

I don't think tire width had anything to do with the cupping. 255 is really the ideal width for 8.5" Wheels -- so that shouldn't have done it. How careful have you been with inflation? You don't appear to have done anything to the suspension and if it isn't alignment -- could be balance. Were the wheels force balanced before installation -- on a bigger tire, I think that is important -- and out of balance can cause irregular wear. Good luck on the solution. Personally, I think that the 235's are too skinny for the 18" Bullitts and degrade the performance of the car. I think Ford OEM'd them because they are much cheaper than 255s.

My .02.

 

A few problems will be causing that (and I have the same problem). Lack of camber adjustment, poor alignment and not being able to rotate your tires often enough if you have a staggered setup. Since you don't have a staggered setup I would just assume you are not rotating the tires enough and might be driving a little spirited around corners I can tell you that the problem you are having is not because of the tires you have.

 

I agree with stupid Here is something else that can cause tires to cup. Worn out shocks. How many miles have you got of the car?

 

Aggressive driving, neg camber setup from the factory. lack of being able to do normal rotations. It all ties together. This is one major reason most performance tires do not carry a mileage warranty. And good luck getting the tires covered under a warranty if more than 1-2/32's are worn off.

 

Another update.

BFG will be giving me a credit towards new tires, but they have to be Michelins or BFG. Fine by me. I will have to pay 43% of the cost of the tires (or a 57% discount, however you want to look at it)

I have 16,200 miles on the car and the tires. I've rotated (directional tires - so front to back) them three times so far. Once around 4000 miles, once around 10000 miles, and once around 16000 miles. They also had to be rebalanced at the the 4000 mile mark and now again at 16000 miles.

I've kept air pressure at 32psi, rotated them, car has been in alignment. I'm not sure what's causing it. Aggresive driving? Maybe...I do take corners fast, but I've never road raced the car.

As far as the new tires (255's), I only need a summer tire, but I do not want KDW2's again. That leaves me with Michelin Pilot Sports at $261 a pop (at tirerack, not sure what the shop prices will be) or I could go to an all season, the BFG g-force super sports at $173 a piece.

If I go with the OEM size, Michelin Pilot Sport PS2's are $232 a piece. In all season tires, the OEM KDWS's are $95! Pretty tempting compared to the others.

 

Ah man, was that necessary? I mean, you didn't have to go and tell everyone I was stupid did ya?

 

Cool hoops. It takes a salesman to call corporate, but it can be done. I only go that far for customers that are nice and not pushy.