brentil

I have a 2014 non-Z51 that is at the end of life of the stock tires. I had been measuring my tire tread depth but I was only checking the first two tread grooves instead of going all the way in and they were at 6/32nd. I was really surprised the front tires were at 6/32nd still at 26k miles when on my 2009 C6 they'd be bald at 25k miles. Well here recently I made a spreadsheet to track my tread depth across the tire and in doing so laid down under the car to measure the inside of the tires for the first time. Come to find out my inner edge of my front tires are both at 3/32nd and look nearly bald... From the pic of my spreadsheet tt's very apparent now that the front wheels are at a much more aggressive alignment than the rears on the C7 or my C6.

My question is on a non-Z51 should my tires be wearing this unevenly? I know "because sports car" so there will be a more aggressive alignment on the car than a pedestrian car but I was surprised to see such a large difference compared to the previous roadsters I've owned.

Of note I diligently ensure my tires are always at a minimum 30 PSI and never let it drop below that for more than a day before refilling. I don't race this car, it's my daily driver. I do get aggressive on it but traffic typically doesn't permit that very often.

Should I get the car re-aligned when I replace the tires which I'm doing this week or is this what it should be?


On the image below O = Outer, C = Center, I = Inner.

brentil

That's odd, when I edited my post to fix a typo it removed the image... re-added.

davekp78

Yes, get the alignment fixed. Do a search for lots of opinions.

brentil

I don't plan on tracking the car so I'll likely go for a more stock alignment. Maybe I can even get it fixed under warranty since it seems rather far off.

Bill Dearborn

How does the car drive? Based on the wear indicated it could be a combination of several things. Here are some rules of thumb I go by.

Negative camber will increase the tendency for the inside of the tire to wear more.
Toe in will cause the outside of the tire to wear more while toe out will cause the inside of the tire to wear more. Toe will cause more severe wear than camber.

The rears look like that the tires may have some negative camber and a little bit of toe out. With toe out the car might tend to wander a little more. GM spec is for close to zero toe with the tolerance emphasizing toe in Vs toe out. Rear toe in provides more stability.

The front also shows negative camber with maybe more toe out there causing some extra wear on the inside. The passenger front tire extra wear could be just a variable or it might indicate a slight problem with the front tires or the alignment. Does the car pull slightly to the left, forcing you to hold the steering wheel turned slightly to the right?

Bill

brentil

Brought the car in for the airbag recall and talked to them about the alignment being covered by warranty and they said it would not be. When I get the tires replaced I'll get a fresh alignment done at that point.