My wheels are out of round, how bad???

[GrayCobra]

The main question is how much out of tolerance (out of round) should a wheel be to 'miss' the spec's for a stock Cobra Wheel? And does this out of round condition affect performance or tire wear?

Every time I got see a pro service guy or gal to get something done I ask the actual mech if they will tell me if/when they find something strange or wrong. I was hopint that none of the new tires would be out of round.

This afternoon while the new Pirelli P Zero's were going on my horse this really nice wheel man say's, "you have three wheels that are out of round".

"What"? I jump up to see. Lemme see, and sure enough we took a few minutes to see that 3 of 4 wheels wobbled and were about 1/4" to over 1/2" out of round and the last one was about 3/4 inch out. Iv'e heard of this problem in the past, but never from a high end wheel. Needless to say I kept the old tires and jumped over the Dealsership. They are gonna put it on a machine tommorrow to give me a decision on the roundness factor.

These are the stock '03 wheels, not the s-chromed one's. I did notice a cupping or valley effect on the old rubber probably due to out of roundness on the wheels.

 

[1995cobraR]

3/4" out of round? That just doesn't sound right. That would shake the car badly at speed. Out of round refers to diameters. Warped usually refers to a "sideways" out of spec (mostly due to hitting a curb or other road hazard).

I've seen tires "out of round" but never a wheel. I've seen alot of wheels warped and/or bent due to above.

Cupping of the tire can also be due to other suspension problems.

I'd double check this opinion with a tire shop that specializes in race and performance cars.

 

[GrayCobra]

Wheels and Tires out of round!

1995cobraR you worte:

3/4" out of round? That just doesn't sound right. That would shake the car badly at speed. Out of round refers to diameters. Warped usually refers to a "sideways" out of spec (mostly due to hitting a curb or other road hazard).

Your right as rain.
Darn thing was shaking when at purchase, but I figured for the price paid I could get new tires and the situation would be good. When I found out the new tires/wheels where out of round I got a bit pi**ed off. After running at the local 1/8th mile (legal) drag way I felt this was just not right. Here's the results in tech terms.

1. The tirerack.com approved local tire installer wasn't as good as we anticipated. However, the customer service people at Tirerack are great at dealing with this kind of thing. I contacted them while at the local Ford dealership, which has both both SVT and Saleen qualified mech's. The car was on the rack getting all 4 tires/wheels "Runout and Road Force" checked. This measures roundness of tires and wheels to EOM specs using a 20k machine specific to mounting and balancing problems. For a passing grade the average road going cars should spec at 20 lbs or less with SUV's and Trucks at 25 lbs.

All 4 tires reported over that, RR 35!, RF 23, LF 23, LR 26. That is both tire an wheel.

Tirerack.com customer service and Pirelli agreed to replace any/all that didn't meet this standard. They send me new one's and I ship this set back...No Charge!

2. The Right Rear wheel was far-out of Ford Motor Company Spec. It must'a hit a curb or ?? and had light scrubbing damage to inside wheel lip area. Woody Anderson Ford (Dealership) is replacing that free of charge since I just bought car there.

3. The tire/wheel Mech dude tells me this problem is common to very wide low profile tires and anyone experiencing shake or rattle might consider checking the road force for their cars while having their suspension looked at. When getting your new tires mounted is the best time to check. His worst experinence is with those 40 and 35 series 20+ inch'ers on the Gangsta Mobiles because they don't want to put the weights on their 'rims' .

4. If you pay out 2-3-4 hundred $ a tire (I recommend) you should get them checked for roundness even if you don't feel anything wrong. The wear out is significantly faster for tires and suspension parts for out of round and imbalanced tires/wheels. Not to mention safety wise.

Now the situation is manageable.

 

[1995cobraR]

Tires and wheel problems

I am glad you got it all fixed. This thread would be a good search for anyone with similar problems.

Congrats to Tirerack and Woody Anderson Ford for solving the problem(s).

One other thing. Can I borrow the car for "test purposes" only?

 

[GrayCobra]

You wanna "Borrow" my BABY?

Thanks for the help and all, but nobody drives my baby who ain't real-close family. Even they must undergo years of intense training and SCREW-TINY. Then comes the insertion of electrified metal rods right next to their heart should they make a mistake and hurt my baby.

 

[1995cobraR]

I agree (but it doesn't cost to ask). I always assume someone else will drive my car like they stole it.

Several years ago I let my younger cousin drive one of my old Fox cars. I lectured him to go easy. He was just out of site when I heard him rev it and drop the clutch. You could here the tires from miles away.