Cupping on Cooper Tires

I've had two sets of these on a 2001 Nissan Altima GXE 4-dr. First set developed severe cupping on the rear (guess I was a bit lazy about rotation). Dealer advised that rear struts needed replacement. Did that (and rotated tires more regularly). Don't know if any more cupping developed on that set, because the noise from the others would mask it.

Anyway, put another set on, and they began cupping on the rear as well--even AFTER new struts.

Didn't have this problem with tires that came on the Altima.

Is this a typical problem with Coopers?

Oh, they are supposedly "low-profile" tires, and the dealer advises that inflation should be 42 lbs.

Also, the Altima DOES tend to be very light in the rear. Some have suggested that I carry a bag or 2 of sand in the trunk to provide weight to keep the rear end from bouncing.

Thanks for your comments.

Reply to
me
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Cupping could be caused by poor balancing, damaged suspension,bad shocks, etc. What does the manufacturer pressures say? 42 pounds sounds awful high for a car with light rear. It will magnify any irregularities and bouncing. Are the tires the right size for the car or are you trying to make it look goofy with low profile tires. This changes the suspension geometry and can cause problems.....

Reply to
Woody
+1 w/ woodz

don't go by what the tire max inflation specs are... go by what the manufacturer states... ~29 psi u can go a bit higher than that w/ no i'll effects.

-> can pump it up higher when you load up your car... that's when the max inflation specs on the sides of the tire comes into play

Reply to
ricebike

I suspect 42 PSI far exceeds the max inflation imprinted on the tire sidewall. You should go by the tire inflation decal attached to the vehicle. Excessive inflation can result in cupping because - just like a properly inflated basketball - they have higher rebound energy that may not be controllable by the suspension. The bouncing causes rythmic "impats between the tire and the surface resulting in cupping. Also, some tires are worse about this than others. The first thing is to adjust the inflation to the recommended pressure and make sure they are properly balanced. Some folks I know do not beoieve rear tires need balancing but, this can also cause cupping especially in conjunction with over inflation. If the cupping starts to appear when the pressures and balance are correct, you may want to have a thrust angle (4 corner) alignmemt done and check the struts for signs of weakness or failure.

Regards

Lugnut

Reply to
lugnut

The size is 205 60R 15, one of the two sizes recommended by Nissan. The other is 195 65R 15.

As for the pressure, two different dealers (one a son-in-law, whom I trust implicitly) say the same. Haven't tried to see if Cooper has a web site with such info.

Reply to
me

Couldn't find any recommendations for pressure on the Cooper web site. All kinds of other stuff, but no pressure. In the "Tire Fitment" guide, they simply say go by what your original equipment specs are in the car's owner manual.

The particular tire is the Cobra Radial G/T, described in the Cooper literature as a "performance" tire.

As mentioned in my reply to Woody, I'm using 205 60R 15, one of the two recommended sizes for my little 2001 Nissan Altima GXE. That is the size that came with it new.

I tend to agree with you on the 29 lbs. I generally keep tires around

30 lbs., but put in 32 when taking a trip (more load in the car, better rolling on the Interstates). AND, I always check pressure and change it with COLD tires--not after they've been driven.
Reply to
me

Thanks, Lugnut,

I agree with you on all counts, but since two different dealers (one a trusted son-in-law), I didn't question the 42.

Understand about the bouncing, balancing, AND alignment. On the Nissan's I've owned, the rear wheels were to be aligned as well as the fronts, so I'm used to that (and DID have it done).

I have, for many years, been sensitive to balance on all 4 wheels. Also, in the older days, I found that many tires were out of round. I had a dealer who would "true" such tires for me. That involved shaving small amounts of rubber from the "high" side. Made for a much smoother ride; and, since the tire wouldn't bounce, less wear made up for the minuscule amount of rubber shaved off.

OK, guys. The consensus is--reduce the pressure. That I'll do. But, the damage is done to two of the tires on my new set, and the roaring is horrific (especially in my little Altima). May do battle with the dealer to see if I can get him to replace them under the Cooper 50,000 mile guarantee.

Wanderer

Reply to
me

wow, the dealers say to pump your tires psi to 42???

which ones are they, just for future reference to my fellow *NICOnauts* to avoid these ill-informed stealerships...

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Reply to
ricebike

Where did the cupping start, front or back, right or left? Cupping in not normally caused by a defect in the tire unless it is way out of balance or manufactured wrong. Are they putting extremely large weights on the tire or large one side to compensate for a way out of balance tire. Are the weights walking on the rim as to throw the balance off? Once the cupping starts there is no way to stop it even by correcting the problem. You may trust your dealer but they are nuts if they insist 42 pounds in a low profile tire is good. You will get a great blast out of one of them someday running at that pressure....

Reply to
Woody

Showed up ONLY on the rear. Hard to tell which side, but seemed to be both.

Interesting about balancing: it was ostensibly done on all 4 wheels. BUT, there are NO weights on the wheels now! My first reaction was shock; but, as I mentioned before, I'm usually pretty darn sensitive to wheel bounce, even in the rear, if a wheel is out of balance (or round). I haven't noticed ANY bounce at all. But, may be worth having them re-balanced.

Also interesting: just had the tires rotated at the selling dealer's shop (free from him), AND the tires are at 29 lbs, on the money, all the way around (the Nissan recommendation)! Usually, a dealer that is on the ball and worth his salt will check inflation when rotating or balancing. Wonder if the dealer backed down on his 42 lb. recommendation?

Reply to
me

Doubt if they're anywhere near you (or civilization, for that matter!). One is in the RURAL stix of Central MO, and the other is in a small town in IL, about an hrs. drive from Chicago.

Reply to
me

The weights fell off. The guy was likely lazy and just glued them onto the clearcoat instead of using the solvent. Or just plain ripped you off.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail >
Reply to
Mike Romain

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