That information you say you received from Tire Rack is completely incorrect, and they are available in OEM 2018 base convertible sizes. Perhaps you asked the wrong question, like is this the OEM tire, and no it is not, but it most certainly fits. They're selling boat loads of them for Stingrays, and many are replacing their OEM tires with these.

Click on the link below.

Tire Rack AS3+ Base 2018 Corvette ConvertibleTires

 

Thanks, your right, I resubmitted the same info and the tires came up. So we'll see.

 

Living in Southern California keep the tires that GM and Micheline spent a lot of time and effort developing. It you don't have to drive frequently when below 40 F they are perfect.

Yep I was surprised when my September 2013 built C7 Z51 chattered much worse than my C6 Z51 with the same width tires. Little info about the reason so I did the research to define the reason. This is the PDF with many pics: http://netwelding.com/Wheel_Chatter.pdf

Significant "chatter" as GM refers to it, only occurred when below about 45 F after I backed out of my garage and made the full lock turn to go down the driveway. That was over 5 years ago and I solved it at the time! When below about 45 F I don't make full lock turns, I turn the wheel less and make a "K" turn! During the slight amount of extra time it takes I think about the smile the 1.2 "g" peak I can archive around the large fountain at the end of my street.

In the PDF you'll see the reason is the very low slip angles the OEM tires have similar to a race car tire. The low slip angles and tread compound make handling great! Once you understand the cause, where you live you'll appreciate the tires and when needed just turn the wheel less! It is only an issue at very low speeds as when making a hirer speed turn the inside and outside tires are loaded differently.

Further proof that the race car tire slip angles are part of the issue is the GM statement that it gets worse in wet weather. Since daughter and family live in San Antonio Heights (Upland) know it's been raining a lot! I have validated the more chatter when the concrete pavement in my driveway is wet. Then there is very little tread surface movement to provide Ackerman compensation.

PS: Let your wife read the PDF, she'll understand there is a reason for the "chatter" and if she drives the car know why she should turn the wheel less for slow speed turns and make "K" turns!

 

Don't worry. It's normal. It sounds awful, but you are not doing any damage. Summer tires will do that. I put winter ones on for better traction in the cold and they don't make a peep. You will have to deal with it until you get new tires. Or make wider turns.