How's the tire pressure? If the tire is overinflated it can lead to cupping.

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2007 G35 Coupe 6MT JWT/Z tube, 5/16 Spacer, MREV2, Stillen Cat-back Exhaust,GT Spec strut brace

Quote, originally posted by G_whizz »

I run mine at 35psi all around.

Depends on where the cupping is, center or shoulders. If the shoulders are fine, but the center is gone, that would be explained by your overinflation.

Recommended is 32 or 35 PSI, can't remember which. Going up to 40 is great for fuel economy, but reduces the contact patch area and also causes uneven wear. This gets worse when you're driving long distance and the pressure goes up due to tire temperature. So your 40 PSI tire which is already 5 PSI too high, is now 7-8 PSI over inflated because of the temperature change.

Those before numbers also look VERY off. Specifically the camber. I was under the impression that we only have 4 wheel adjustable toe. If that's the case, how did the alignment tech magically add .8-1 degree of negative camber to the front wheels? Same with your caster. 2.8 degrees is WAY out of spec.

Am I reading the report wrong? I'm seeing before being the initial reading and actually being the current reading after adjustments. Is that correct?

Where was this done?

F/S:G35/350Z/FX35/Altima Grounding Kits

Quote, originally posted by Mr1der »

go see her, have the most brutal sex ever, then drink most of her milk from the carton and leave.

It looks like the tech tried to adjust the toe and ended up making the camber worse (looking at the camber before/after numbers). Not his fault though because the camber is not adjustable.

Is your car lowered? A new set of SPC upper control arms will give you the adjustments you need, but at a cost. I have them on my car and they have worked out great for me.

I've said this over and over. CAMBER doesn't cause tire cupping. The toe will destroy a tire in a matter of a few hundred miles if it is completely out of spec. Out of spec camber will cause the tire to wear faster on the inside or outside depending on too much negative camber or positive camber.

Now on to the tire pressure issue. During accident reconstruction school, we learned that running around 38-40 psi was optimal. I saw where someone mentioned that if you were at 40 psi cold and then the tires heated up you would be another 7-8 psi higher. That is not the case. We tested the theory and set tire pressure cold @ 32-35 psi. When tires were hot, they were 8-10 psi higher (40-45). When they tested 38-40 psi cold and the numbers only increased 4-5 psi. We also learned that running in this 38-40 range, helps with side wall flex(rolling over), increased mpg, better handling and less damage to the tires from heat. As you can see from the tests the tire is only heating up half as much as running a lower colder temperature. We all that heat is one of the destroyers of tires along with alignment specs.

Factory Service Manuals can be found here

The Toe is pretty far out of spec BEFORE. The toe is what will kill your tires. I burned 20K miles of tread in ~50 miles with bad toe. It will trash your tires. Keep an eye on the toe.

Also with 19" rims, depending on the size of the sidewall, I would be between 37-40 PSI. Extra protection for the rims + better handling/response + with the stiffer sidewalls will wear tires evenly.

The 7-8 PSI was 5 PSI over spec plus the 2-3PSI due to heat for a total of 7-8 PSI.

When I first lowered my car, I had increased front tread wear on the inside because the camber could not be adjusted back into spec. To me, that is the same thing ... increased tire wear which is why I put in new adjustable upper control arms as soon as they became available. My fronts are wearing perfectly even now.

I'm not gonna argue with you, not worth my time.