More C8 Corvettes Dealing with Faulty Valve Springs As GM Extends Build Window for Affected Engines


More C8 Corvettes Dealing with Faulty Valve Springs As GM Extends Build Window for Affected Engines

Photo Credit: Chevrolet

It was exactly one month ago that GM issued a service bulletin regarding a batch of bad valve springs that were used across the GM V8 line-up that includes the 2020 Corvette’s LT2 engine. Drivers may experience engine misfiring and a check engine light when one of the valve springs fails.

In that original TSB, General Motors stated the faulty valve springs were used in the production of the engines from June 1st – September 15th. However, more and more Corvette owners whose engine build dates were past September 15th were also experiencing broken valve springs.

Because these customers were outside the production window of the TSB, they not covered by the full fix which was to replace all the valve springs. Instead, only the broken spring was replaced. As some of the drivers were on road trips, you can imagine being somewhat fearful that one of the other springs will also break while on the road.

Fortunately, GM has updated the techlink article and has expanded the window to include these latest cases. The new end date for affected 6.2L engines is now October 7th, 2020.

Valve Spring Illustration

Photo Credit:

Now for some bad news.

Because the fix requires all valve springs to be replaced on the 6.2L engines, you can imagine the demand this has put on sourcing replacements as 16 new springs are required for each affected engine. Owners all needing replacements in addition to the C8 Corvette include those who own the Chevy Silverado and GMC Sierra pick-ups, as well as Camaros with the LT1 and LT4s. Some of those with the issue report their dealerships warning them of extended waits as everyone scrambles to find the replacement springs.

Also keep in mind that the new end date references the build date of the LT2 engine and not the production date of the car, which generally happens weeks after the engine has been constructed at the Tonawanda engine plant in New York and then shipped to Bowling Green, KY for installation. So affected Corvette engines with the bad valve springs could around longer than originally expected.

Source: via

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  1. Its funny, all the high tech equipment in the C8, and something as simple and low tech
    as a valve spring is breaking on the new cars. I bought a 67 L71 427/435..New,and a few months after I got it I had to take it in for a broken valve spring…I guess, nothing has change. I assume these valve springs come from a 3rd party supplier. Usually you can keep
    the quality control better, when everything is make, in house

  2. Wonder if you can find out if your car was held for OC and had the valve springs replaced . My vette was produced on September the 21 was held until October 12. 450 miles on it now but still concerned .

  3. This is another reason not to buy a big time production vehicle like a Corvette, during it’s first model year. There are going to inevitably be, various issues that come to light. This is true under normal circumstances, let alone during a period when the production factory experienced numerous periods of shutdown due to the coronavirus and supply chain issues, on a related level.

  4. The springs are made here in North America, well actually Mexico if you want to be a little misleading, well actually the same factory that made the indestructible C7 Wheels.

  5. All these issues and it still valued at 20-30k over Msrp. I want one but it’s a hard pass for now…..

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