Both insides of rear wheels gashed??!!

[Teej]

(I meant tires, not wheels)

I just tried to get under the back of the car to see where the rear valence attaches so I can pull it off for repairs. Previous owner had a boo boo and one of the valance columns broke. Anyway, I noticed my drivers side tire had some nice healthy gashes, so i looked over at the passenger tire and saw some smaller ones.

We JUST got back from 400+ mile trip...thank goodness we made it. Anyway, is this just coincidence or are there other issues at play? Need to know before I buy some more rubber....

Currently it has 275/30/zr19 Bridgestones. Wheels are 19x9.5.

I'll add a photo once I get back from the store... my current jack is about 1/4" too short to fit under the jack point. Time for a new jack

 

[Hapa88]

Sounds like the typical rear tire wear for the NSX. The camber angle along with the aggressive rear toe causes the insides of the tires to wear down to the cords pretty quickly. This is common and normal.

It usually looks something like this (note the outside edge looks like it has plenty of tread):

As for jacks, I just picked up the aluminum one from Harbor Freight and it fits under my car without any issues (and I'm pretty low).

http://www.harborfreight.com/automo...act-aluminum-racing-jack-68053-html-7814.html

There's Coupons every once and a while to get this jack for $59...

Here's an expired example:

 

[Teej]

Well the tire tread is fine, but the inside rim lips have slight rash as if someone drove this through a car wash at some point.

 

[docjohn]

how old are those tires,and what is the pressure in them?

 

[Teej]

how old are those tires,and what is the pressure in them?

I don't know the age of the tires, only that the rears are different in brand than the fronts (Yoko front / BStone rear). I've only had the car for 3 weeks. The tire pressure on the back, both sides is 28psi

 

[docjohn]

my first impression was that the tires may be dry rotting and be underinflated putting extra stress on the sidewall......anyway the optimal cold pressure should be 38-40 psi so you are way off....just replace them and routinely check pressure everytime you fill the gas tank.

 

[Hapa88]

What suspension are you running?
Check out this thread where mcano wore out the inside of his tire because it rubbed against the strut body of his Bilstein Struts. His solution was to run spacers.
http://nsxprime.com/forum/showthread.php?t=128958

 

[Teej]

What suspension are you running?
Check out this thread where mcano wore out the inside of his tire because it rubbed against the strut body of his Bilstein Struts. His solution was to run spacers.
http://nsxprime.com/forum/showthread.php?t=128958

I had that thought too when I was looking at them. It looked like they would clear just fine, but when I saw the inner rim rash..make me think that maybe under a hard damper from a road hump at speed, that the tires might be rubbing on the strut tower. I have Tein Flex coil overs.

I thought about popping out the wheels recently (no pun given the situation) with 15mm spacers.

 

[Teej]

my first impression was that the tires may be dry rotting and be underinflated putting extra stress on the sidewall......anyway the optimal cold pressure should be 38-40 psi so you are way off....just replace them and routinely check pressure everytime you fill the gas tank.

Yes, way off they are. I thought 28 sounded low too, but then when they both came in with the same pressure (shrug).

 

[Moses]

How about a automated car wash.

 

[docjohn]

hapa88 is one of our wheel and offset gurus,what wheels specificly and offset do you have? he may be correct you might have shock interference on load.

 

[Teej]

hapa88 is one of our wheel and offset gurus,what wheels specificly and offset do you have? he may be correct you might have shock interference on load.

Moses, the carwash thought immediately came into play when I saw the inner rims were slightly rashed.

docjohn, I have 19x9.5 TE 37's on Tein Flex coil overs. I am actively looking into spacers and are looking into 20mm which is just under an inch.

I do not know my offsets unfortunately but I bet they are printed on the hub side of the wheels.

 

[nsxtasy]

The gashes in the photo look like actual gashes. They do not appear to be the result of rubbing. Rubbing creates a groove pattern that is uniform all the way around the tire, which those aren't. I agree that it's possible the tires are old or defective, or it's possible that they were caused by something extraneous to the car (such as at a car wash). Either way, you'll need to replace the tires, but the new ones should be okay.

You can determine the age of a tire by reading the DOT numbers on the tire sidewall; you may need to take the tires off the car to do so (they're usually on one side of the tire or the other, but not both, so if you're lucky they're on the outside sidewall, otherwise they're on the inside). Here's how to do so:

Determining the Age of a Tire

Here's more info about tire aging:

Tire Aging – Part #1
Tire Aging – Part #2

 

[nsxtasy]

Sounds like the typical rear tire wear for the NSX. The camber angle along with the aggressive rear toe causes the insides of the tires to wear down to the cords pretty quickly. This is common and normal.

I've never, ever had my rear tires wear unevenly in the way you describe and picture. I'm not saying yours didn't, but mine never did. And my car was aligned with the aggressive rear toe of the original alignment specs, not the modified alignment specs.

My fronts, though, are another matter, and have indeed worn on the inside edge of the tread more than the rest of the tread.

It's common and normal for front tires, not rear tires. However, it may happen if you have a non-stock alignment, such as on a car that's substantially lowered.

 

[fkong777]

That is a combo of old tires that ran under inflated.

 

[goldNSX]

It's common and normal for front tires, not rear tires. However, it may happen if you have a non-stock alignment, such as on a car that's substantially lowered.

He has already stated that he's running a TEIN on the car but didn't say how low.

Here's my rear tire. I was very surprised as my car isn't that low, has stronger stabilizers and a camber of 1.7 degrees. I know where this comes from: spirited driving with aggressive slow-cornering.

I once had a Bridgestone showing a split in the rubber (but radial) on it's outer side (not it's thread pattern) This was (high likely) caused by rolling over a stone high and sharp enough to overstress the sidewall.

Yours looks like an overstressed sidewall too, mainly due to the underinflation.

 

[Teej]

Makes as good of sense as any goldNSX. new rubber last week

 

[goldNSX]

Your car is pretty low. Much camber due to very low ride height and low inflation puts heavy stress on low-sidewall tires. It even puts heavy stress on the inner sidewall if the tire is inflated correctly.

Sidenote: I once had a 3-piece rim (Axia, made in France ) that couldn't sustain longterm usage (no track) and showes small little cracks on the inner lip, very scary but this was caused by the rim manufacturer who went bankrupcy some time after.