C7 Corvette Z06 Overheating Issue | Case Closed!?

Corvette Z06 On Track

Z06 Overheating | By: Chris Trautman

GM extends the warranty on the 2015-2018 Corvette Z06's for a proven Z06 overheating issue. Effective 12/23/20, the new warranty coverage will take care of any owner who has a C7 Corvette that displays a history of overheating or service visits related to the overheating problem.

Coverage Details:

• 7 years or 72,000 miles from car entry into service
• The owner needs to provide proof from videos, pictures, or diagnostic codes.
• GM will replace the radiator on all (proven issue) Z06 automatic and manual transmission cars with an upgraded 2019 version. Incidentally, 2015-2018 radiators have been discontinued from GM, and the only available options to order are the 2019 part numbers. 
• Automatic Corvettes will get a transmission calibration update.
• GM made no mention of replacing the Supercharger lid as part of the warranty coverage. 
•  See Details on the Supercharger Lid Upgrade Here

What Does the Z06 Overheating Repair Cost?

If you have a valid warranty, claim the upgrade will cost you nothing!

If you are GM, the radiator at GM cost is reasonably low, and the labor is probably the most expensive part of the upgrade.

If you are not covered by warranty you can have the 2019 Radiator parts for around $200. If you are a DIY type that wants to upgrade the radiator, you could potentially do it yourself. 

The transmission calibration is all software, so GM's cost is probably nothing since it's most likely the same out of the 2019 Z06 corvettes calibration. If you wanted to upgrade on your own, we are sure in the future; GM will offer this; we don't have any idea of the price yet. Another couple hundred as a best guess.

Z06 Overheating | How Many Corvettes Are Affected?

Just a little over 33,000 cars are affected by the warranty extension. Not sure how GM figured the 5% number for actual reported customer cases but that would assume 1650 Z06 Corvettes have claimed an overheating issue to GM. Some owners may have taken matters into their own hands and fixed them with their own upgraded cooling hardware.  

2016 and 2017 Corvette Z06's account for the highest production concentration on the C7 Z06 Corvette with 21,548 total Corvettes produced. The 2019 Z06's are not included in this tally since 2019 is considered the Corvette without overheating due to production changes. 

2015 and 2018 Corvette Z06 production numbers were very low due to first-year production and plant closures in 2018. 

 What does this mean? Well, nothing; we wanted to share a different perspective of the Z06 overheating issues by the numbers!

What If You Have Had The Z06 Overheating Issue?

• If you have already paid for repairs for a proven overheating issue, you will request reimbursement from GM for the cost to repair. If you meet the warranty limitations, GM will cover you.
• If you currently have a Z06 Corvette with an overheating issue, work with your dealer to resolve it.
• Regardless your GM dealer is your best place to start for more information. If the dealer is unable to help you or you wish to upgrade further, please come back and visit our suggestions for upgrades.

Hot Water | What Has Changed On The C7 Corvette Z06 Through The Years for the Overheating Issue

Early on in the C7 Z06 program, an overheating issue threw the Corvette team for a loop. They state it affected less than 5% of Z06's. GM had been fairly transparent through the problem and claimed that engineering standards had to change, validation of new hardware changes had to occur, which then required production changes. By that time, production was winding down on the C7 program. That did not mean they walked away and did nothing. It's easy to be critical of GM's handling and how things should have been done differently. Hindsight is always 20/20, and it's easy to be an armchair quarterback.

The last thing GM wants to do is damage the Corvette brand, but for some, it has been too little too late.

We have researched and found what they have changed to fix the issue through the years:

• Intercooler lid upgrade (2017), more here
• Supposed changes to hood cooling vents (we could not verify as no part number changes or obvious design changes are visible)
• Engine computer calibrations
• Bleeding of the intercooler system to remove air pockets
• Changed and increased the radiator capacity with dimensional changes two times, latest PN is found on 2019 Corvette Z06 parts index.
• Installing aux radiator on manual transmission cars, adopted from automatic cars
• Extended warranty coverage

Hot Air | What About the Overheating Lawsuit?

As of September 28, 2020, the class action lawsuit has been "Settled" with "Prejudice," which means the case cannot be re-filed.  This lawsuit never reached class action status.  

It would also appear under an assumption on our part that the settlement (see here) on September 28th, 2020 and the following warranty extension on December 23, 2020 are connected somehow.

But since the settlement is not public knowledge, we will never know. GM has also not publicly acknowledged the settlement or any terms. It appears all parties have won in the overheating case on the surface.

Only time will tell if the fleet of Z06 Corvettes or their owners have closed the door for good over the overheating issue. 

Chris Trautman @ Corvette Assembly Plant 2019

About Us: Corvette Web Central | Owner Bio: Chris Trautman

Established in 2008 by Chris Trautman, Corvette Web Central quickly grew into one of the top leading Corvette enthusiast websites globally. 

"This website is a passion of mine just as much as being a Corvette owner," says Chris.  He was frustrated trying to find information on the internet about Corvettes which was was not biased or influenced somehow. 

He has owned three Corvettes over the last twenty years and does not plan to stop owning one anytime soon.

C7 Corvette Morimoto Tail Light

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