NineVettes

Yesterday, I left a track day a bit early when I notice my '19 M7 Z06 had picked up a little vibration. It has the stock wheels & tires. I suspect that the left front wheel may be either bent or cracked. Perhaps if I am very lucky, just a wheel weight fell off - it got pretty hot out there in the afternoon - around 90 degrees. Tire is holding air pressure. Vibration appears to be somewhat cyclical and occurs at various speeds.

So, my questions:

1. My Z was manufactured fairly early in the '19 run (bought it last Sept). I thought I saw on here that GM changed the wheel supplier sometime late in '18 and the newer wheels may be better quality?
2. When I bought my Z from Criswell, the one extra thing I bought was a "Maximum Tire and Wheel Protection" policy issued by Maximus Auto Group. Does anyone have any experience with this policy issuer - are they ok to work with? I don't have a lot of free time to waste running around in circles with them.

I have always thought that one of this car's few weaknesses was its wheels and tires. Besides the oft reported problems with wheel integrity, running 19 and 20 inch wheels with runflat tires is the worst of both worlds in terms of performance and ride quality IMO. When I used to do a lot more track time years ago, we rarely used wheels larger than 18" If I had to replace these wheels, I would get rid of these cheap and very heavy Chinese (Mexican) cast wheels in favor of a forged 18/19 setup shod with non-runflat tires (also too heavy). I am sure that combination would save me around 10lbs per wheel in un-sprung weight.

Mr. Gizmo

if its holding air thats a good sign. You might have knocked a wheel weight off or bent a rim. Your wheel protection package should cover it. Call the company Take it to a tire and wheel shop the wheel insurance package recommends. Don’t tell them you were on the track

Bill Dearborn

My first suspicion would be a lost wheel weight. They come off quite easily when the brakes heat up the wheels. 90 degree ambient temp doesn't affect the weights much but a wheel so hot you can't touch it with your bare hands will lose stick on weights. I usually cover my weights with aluminum duct tape to reflect brake heat off the weights and to help hold them in place.

Second I would suspect rubber build up on the tire.

The reason I say this is because even if you did bend the wheel it is highly likely you wouldn't notice a bend on the edge of the rim when driving unless the bend was severe. A slight bend doesn't really change the wheel's balance and you don't feel the irregularity in the wheel if the tire stays the proper shape as it rotates. My wife dinged two of the rims on our Malibu by driving through a hole at the edge of a road. Couldn't feel a thing when driving but could definitely see a flat spot on the edge of each wheel. The wheels didn't look good but still worked so we never had them repaired.

Bill

383vett

Most of the bent wheels occur on the rears. I'm not saying front wheels can't be bent but not as frequently.

Larry M

I bought the same W&T policy as you through Criswell. Bought it after my first bent rim because I wasn’t taking anymore chances on a car with less than 500 miles. Long story short, very minor bend which was fixed with a wheel weight...or maybe the dealership was trying to rip me off on buying a new wheel and new tire.

6 or so months later, cracked a different wheel. Process through them was pretty good, only problem was my wheel is part of a GM package so the first place sent the wrong wheel. Ended up going through the stealership which wanted nearly double for the wheel, didn’t make any difference to the insurance company, I was just trying to help them out of principle

NineVettes

As the OP, I appreciate everyone's responses - thanks! I am still fairly new to north central Florida, but I did find a local Discount Tire shop which has a good rep for working with performance cars. Gave them a call yesterday and they said they have seen this problem before with the 3 C7 Z's they worked on. One had weights missing, two had bent/cracked wheels - all of them were tracked. Soooo, I am a bit more hopeful that maybe it was just the loss of a wheel weight. We will see - I will drop by there later next week as my schedule permits - already bought the aluminum duct tape at Home Depot - with fingers crossed.

Not a good time of the year to be thinking about big purchases since I need to do both normal tax filing and business estimated quarterly payments to the infernal revenue service and it will not be pretty. If I need to, I will utilized the wheel insurance policy I bought from Criswell at the time I bought my car - good to know someone has used it.

Mikec7z

ive bent 7 wheels in 2 years.

I believe you've bent your wheel.

Dont bother wasting money on repairing it, it will just bend again instantly. Call Bob at house of wheels, he has real oem wheels for sale, at the lowest prices, and he is down here in Ft Laud. My good friend just saw him today as a matter of fact.

Mikec7z

you can diagnose the wheel being bent if you can get the car up the lift, in neutral, to spin it, and keep your eye on the inside bead/rim. Its very obvious if its bent.

blackbirdws6

If you tracked the car reasonably hard and heated up the rubber real nice (melted wear?), that can impact the wheel balance. I remember when I really chewed up my tires after a track outing. I had gumballs of rubber stuck to the tire surface. Actually doing a slight burnout cleaned off the excess rubber and the car road better. I've bent 5/cracked 1 wheel and have since moved on to a set of Forgelines. Insurance was replacing the wheels but I didn't like the ride issues and hassle of getting the wheel replaced.

badhabit_wb

I bet it's a tire weight or scrap rubber you picked up on the track. I got tired of using my street tires on the track and ruining them so I bought extra wheels and never run my street tires on the track. Hope it's an easy fix.

Mikec7z

i think he has a 50 50 shot

NineVettes

Well, took a little time out of my crazy schedule to get the car checked out today at a really good Discount Tire store which has a lot of high performance car experience. As I suspected, the left front wheel is bent! It was obvious when they were rotating the left front wheel on the balancing machine. Right front was ok. Shame on the Corvette Team for producing a track car with such marginal, crap wheels. An $88,000 MSRP car that is supposed to be track oriented should come from the factory with forged wheels - period. Even if for some inexplicable reason, in-house testing did not reveal the inexcusable poor integrity of these wheels, the C7 Z has been on the market long enough for GM to have addressed this issue with their track model. Inexcusable. This is my 10th Vette. Previous Vettes included a '93 ZR-1, 2002 Z06, 2010 Z06, 2011 ZR1 - all which were tracked. NONE of those cars EVER had a wheel problem. My '19, on its first track day, comes up lame.

Fortunately, I bought the extra wheel insurance from the dealership, and the policy will be used shortly. It is sad that I even need to shell out the dough for that kind of extra insurance to protect against GM's penny-pinching. Doubtful that will track this car again until these crap oem wheels are replaced with forged ones. I will go 18-19 with whatever forged wheels I end up with. And I certainly will not put run-craps on those wheels with their unyielding sidewalls.

Vendors, please refrain from piling on with PMs about your products - I know about them now. And, I will reach out when ready to buy wheels..

badhabit_wb

Sorry to hear that the wheel was bent. Factory wheels aren't the only ones getting bent on these cars. The width of the wheel and placement of the hub is the problem. All of the stress is concentrated on one side of the wheel rather than close to the center.

Carvin

So you bent it at the track? Any idea how?

NineVettes

Perhaps, this might occasionally happen to a non-factory wheel, but I have not seen or heard of an occurrence, where OTH, there are many, many reports of OEM wheel failures. Never understood the mania to put 20, 21 inch wheels on cars that will be tracked. Then sourcing the wheels to such a low quality producer to save a few bucks per car. I mean honestly, you are charging $80k and up for your track car, how much per wheel more would it cost to source out 40,000, 50,000 forged wheels? An extra 300 or 400 bucks per wheel at those quantities? Did GM think that a Z06 buyer of this fairly expensive vehicle would not buy it if the MSRP was $2k higher?

I think using 18 and 19' forged wheels in conjunction with non-run-flat performance tires will eliminate the bending problem 99% of the time. And that does not even take into consideration the possible saving of around 10 lbs or so of unsprung weight per corner. Depending on who you talk to, that 40 or so lbs reduction could equal around 120-160 lbs of sprung weight.

Bill Dearborn

How was it bent? Was it on an edge or was it bent laterally through the hub?

Bill

badhabit_wb

I know they could have used better wheels but you could go from one end of the car to the other with that same frame of mind and the car would be 300,000 instead of 100,000. For the money we have a great car. For those of us that push it beyond the factory limits there is a price to pay.

Cercone

Tire & Wheel insurance $800ish for 5 years. Best insurance money I’ve spent, I get a new tire for a nail in it. Scratch the rim they repair it, any bent or cracks it’s replaced.

tertiumquid

The problem doesn't happen just to tracked cars. My'16 has never been tracked or pushed beyond any limits. I had 3 bent wheels and two cracked in 9K miles. Switched to forged and non-run flats and no problems since.

As far as wheel insurance is concerned, it's fine except all you get is replacement OEM cast wheels. Groundhog day...

NineVettes

I can only guess. The left front wheel would be taking more "punishment" than the others. This was a technical road course and I was clipping apexes the best I could while building up my speed during the session. Clipping the apex means getting a wheel up a bit on the raised portion of the track there. Never happened with stock wheels on any other Vette I had...