Grand Sport GY Tires on GS is BS

[C6Maverick]

Bought a 2012 Centennial Ed GS and was told by the dealer that they were told by Chevrolet not to align until 5-7K miles. My right rear tire was showing wear,so I took it in at 8K. Dealer said car was in alignment, but that tire would wear the fastest due to it is the power wheel (let's see limited slip, positivetrac......maybe not!). After venting with my local car club, I see a trend with GS owners on premature tire wear. Some have had all 4 replaced and others justa set, but had to get the GM Rep involved. I'm going back this week and insiston some action.
If they won't acknowledge, while my car is on display at our national event, I'll make sure there are mirrors on each tire with placards annotating tirebrand, mileage expectancy, dealer name, service manager and dealership manager.And of course information on links on different Vette forums denouncing these tires and alignment specs.

Maybe after Eli Manning puts about 5-7K on his GS, he'll be a spokeperson for US! :duh

 

[vett boy]

I've gotten 40,000 miles on a set of tires both Goodyear's and Michelin's .If you don't do a lot of true performance driving and keep your speeds below 150 mph I'd change your alignment spec .Send me via PM your personnel email address and I'll send you the spec .I use.

 

[Gripey]

I'll have to say that I got a huge surprise yesterday morning. I have started noticing some vibration on my GS and thought I might just need the tires balance. I put it up on a friends lift yesterday morning just to look it over and discovered that all 4 tires had the inside tread severely worn :ugh The rest of the tread is in great shape.

The car has 14000 miles on it. Is this very common? I have never had the car aligned (yes, I'm a dumb butt). I guess I didn't think I need to have a new car aligned so soon....

 

[Hib Halverson]

I'd say, looking at those pictures, you have two problems...

1) slight over inflation. For normal driving, I'd drop my pressure a few psi
2) a little too much camber. I'd change the rear camber by about a quarter degree negative

Even with a limited slip, rear tires will wear unevenly, left to right. I've experienced that with both my C4 and my C5.

 

[ßill]

Won’t comment on the GS, but after 60k miles and 7 years on a set of GS/D3s on my ’90 ZR-1, I can’t complain about my GoodYears.

 

[rkoblin]

Tire Wear

I have noticed the same thing....9500 miles and the tires are not wearing (2010 GS) evenly. Firstly the tread wear number is 220 so they are very soft and if you live in the south the heat from the pavement also has an effect. I priced Mich, they have a tread wear of 230. Goodyear and Michelin will not warrant any of these specialty EMT tires for mileage wear. The only way to beat it is to get a standard non emt tire if you wish to gamble with no spare.
priced new tires at Costco, new Michelins front and rear mounted and ballanced, $2100.


I guess if we can afford the car we can afford the tires sigh!:ugh

 

[CentennialGS]

I have noticed the same thing....9500 miles and the tires are not wearing (2010 GS) evenly. Firstly the tread wear number is 220 so they are very soft and if you live in the south the heat from the pavement also has an effect. I priced Mich, they have a tread wear of 230. Goodyear and Michelin will not warrant any of these specialty EMT tires for mileage wear. The only way to beat it is to get a standard non emt tire if you wish to gamble with no spare.
priced new tires at Costco, new Michelins front and rear mounted and ballanced, $2100.


I guess if we can afford the car we can afford the tires sigh!:ugh

Agree with the above post. The 220 rating and soft compound do go a long way in how long the tire will last you based on your driving habits. You saw a post or two above where people report your same issue while others report long mileage out of their GS tires. But other than the GS, you have many choices, a little cheaper than the run flat GS:
Vredesteins ultrac sessantas (not sure if they make a 325 in 19)
Hankook V12s
Potenzas RE050s with 280 rating
michelin pilot super sport
Nittos, INVOs or NT555s

 

[tlmgsc2010]

Get it alinged

Agree with the above post. The 220 rating and soft compound do go a long way in how long the tire will last you based on your driving habits. You saw a post or two above where people report your same issue while others report long mileage out of their GS tires. But other than the GS, you have many choices, a little cheaper than the run flat GS:
Vredesteins ultrac sessantas (not sure if they make a 325 in 19)
Hankook V12s
Potenzas RE050s with 280 rating
michelin pilot super sport
Nittos, INVOs or NT555s

I just came back from a VIP tour at the plant. They confirmed the grand sports are aligned for aggressive driving and not for every day driving. The tires will ware badly on the inside corners without proper alignment. I'm having mine done as I type this note but the dealer has already found the alignment was way off even from spec. Mine is a DD driver so this should really help.
i'll have the actual numbers once they finish.

 

[catbert]

After owning a couple C6s, I can tell you that my experience is that the inside wears much faster with factory alignment specs. It's well worth the dollars to get the car realigned to correct the wear issue.

 

[tlmgsc2010]

Final numbers

I just came back from a VIP tour at the plant. They confirmed the grand sports are aligned for aggressive driving and not for every day driving. The tires will ware badly on the inside corners without proper alignment. I'm having mine done as I type this note but the dealer has already found the alignment was way off even from spec. Mine is a DD driver so this should really help.
i'll have the actual numbers once they finish.

The factory camber was found to be set at -1.3 to -1.4. All out of spec. ( -1.1to 0.2)
The other specs were also off in most cases beyond the required specs.

You can actually see the difference now over what I had before. As a small test the wheels had a 1" gap at the top with a simple level placed vertically across the tire sidewalls ( tight on the lower sidewall) Now it's almost dead on ( top to bottom ) with a slight gap on the top but that would agree with the slightly camber required.

As I said you can really see the difference from viewing from behind the car. Sure glad I did this. Tech said the car as set at extreme aggressive setting or beyond what would be expected.

 

[catbert]

I just came back from a VIP tour at the plant. They confirmed the grand sports are aligned for aggressive driving and not for every day driving. The tires will ware badly on the inside corners without proper alignment. I'm having mine done as I type this note but the dealer has already found the alignment was way off even from spec. Mine is a DD driver so this should really help.
i'll have the actual numbers once they finish.

What did you reset the alignment at? I'm bringing mine in before it's too late.

 

[tlmgsc2010]

Actual numbers set

What did you reset the alignment at? I'm bringing mine in before it's too late.

The LF was set -0.1 camber
6.9 caster
.06 toe

Rf, got -0.1, 7.4, 0.07 respectively.

Front cross camber, 0.0' cross caster, -0.5' cross SAI 0.0


LR and RR were set at -0.2 camber and -0.01 toe.

Rear cross camber -0.1 total, total toe -0.03, and trust angle at 0.00

As I said you can see the difference so I know my tires should ware a lot better now than as before with the Mfr set up.

Every car, it's tires and driver are different so it may be worth some trial and error. These settings are at the low end of the allowable range while the factory sets them at the extreme high end or in my case beyond the extreme spec'd range.

My car only had 1600 miles on I had it checked and then re-aligned.

By the way I have Michelin ps2's on the car set at 34#s.

Hope this helps those who want to keep your tires a lot longer than the guys who track and burn.

 

[catbert]

Thanks!

 

[CentennialGS]

very interesting, thanks for posting this guys. I will be getting mine aligned tuesday.

 

[JJS]

Tire wear

I'm looking at C6's and I've been noticing comments regarding tire wear, or tire problems in wet conditions especially with the wide bodies such as the Z06's and Grand Sports.

I read one of Hib's posts from earlier this year when he bought his new Z and swapped out the stock tires with P2's after picking up his car for the ride back to CA.

I might be looking at a new GS this weekend and I'm not sure I'll be able to pull a tire swap off after spending so much $$ on a new car.
I won't make it a habit of driving in the rain but the tire wear concerns me as putting new tires on a brand new car would be a hard one to pull off with the wife - even though I understand.

What is GM doing to help out with this problem - if anything?

 

[tlmgsc2010]

Tire swap or not

I'm looking at C6's and I've been noticing comments regarding tire wear, or tire problems in wet conditions especially with the wide bodies such as the Z06's and Grand Sports.

I read one of Hib's posts from earlier this year when he bought his new Z and swapped out the stock tires with P2's after picking up his car for the ride back to CA.

I might be looking at a new GS this weekend and I'm not sure I'll be able to pull a tire swap off after spending so much $$ on a new car.
I won't make it a habit of driving in the rain but the tire wear concerns me as putting new tires on a brand new car would be a hard one to pull off with the wife - even though I understand.

What is GM doing to help out with this problem - if anything?

I would say that all depends on your daily driving vs tracking time. You can count on the stock goodyear's for not being comfortable for every driving especially while driving around in temperatures around the mid 40 or so. They slide like crazy. If I'm tracking, the stock tires will soon be history but good for hooking up. I changed my non-track car out with Michelin PS2 's which are great for traction in wet cooler weather, hook well, and have a smoother drive to boot. Not to mention much better mileage expectations. 40k plus. The only issue is that the PS2 will fit a GS or Z06 wider rears. They do not come in that width for "zero pressure" PS2's.
i actually put altered width rear OEM's on my rear to work for All Season ZP-PS2. I probably have the only late model GS out there with this set up. It's expensive to do but if you're limited $$$$ and don't drive in low temps I'd drive the GY, let them wear out and buy the PS2 non ZP's.

My 2 cents.

 

[JJS]

>. You can count on the stock goodyear's for not being comfortable for every driving especially while driving around in temperatures around the mid 40 or so. They slide like crazy

I swapped out the GoodYear's that came with my LT-1 for the very same reasons, and the tires (GT+4's) were like brand new. In fact, I still have them.
It only cost me a few hundred for new rims and tires for the C3 - it certainly will be much more costly to do the same for a new car, and like I said, much harder to justify. That's IF I buy.

Thank you for sharing your experience.

-JS

 

[midyearroadster427]

michelins are now making their super sports in sizes that fit the Grandsport rears....they had just the fronts in the correct size but now are making the rears with what someone told me a 20,000 mile warranty....so when mine wear out at some point ...Michelins here I come.


Also...someone told me to check out the alignment specs on the pfdt? website....their street set up is great for street driving cars ...or so I am told...

 

[catbert]

I'm looking at C6's and I've been noticing comments regarding tire wear, or tire problems in wet conditions especially with the wide bodies such as the Z06's and Grand Sports.

I read one of Hib's posts from earlier this year when he bought his new Z and swapped out the stock tires with P2's after picking up his car for the ride back to CA.

I might be looking at a new GS this weekend and I'm not sure I'll be able to pull a tire swap off after spending so much $$ on a new car.
I won't make it a habit of driving in the rain but the tire wear concerns me as putting new tires on a brand new car would be a hard one to pull off with the wife - even though I understand.

What is GM doing to help out with this problem - if anything?

As mentioned, the tire manufacturer is making the tire that GM wants on the car, and GM has not changed the alignment specs to reduce premature inside tread wear, so the obvious conclusion is nothing. The C6 gets spectacular skid pad numbers because of the aggressive alignment and tire compound, and that's the whole point. The numbers look good in magazine tests, and during track days. If you want to set up for every day driving and cruising, realign the car, and replace the tires with something harder when they wear out. With a realignment, you should get 20,000 miles on the OEMs. That's not terrible for a soft compound performance tire.

 

[catbert]

Also...someone told me to check out the alignment specs on the pfdt? website....their street set up is great for street driving cars ...or so I am told...

Does anyone know anything about the referenced website...never heard of it, but I'd like to see their take on it.