Attention Valve Spring Failures/Concerns
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Attention Valve Spring Failures/Concerns
GM has a timeframe on spring failures it seems. This affects all of the V8s from the 5.3 in Trucks/SUVs, 6.2 in Corvette/Camaro/Trucks/SUVs and the 6.6 gas engine in HD trucks. 6.2 is the one of most concern it seems per their instructions below.
Seems like they have a window of where a bad spring or springs might be possible to be found.
Seems like they have a window of where a bad spring or springs might be possible to be found.
#PIP5752A: Service Engine Light misfire engine noise With DTC P0300 P0106 P0506 - (Sep 22, 2020)
Subject: Service Engine Light misfire engine noise With DTC P0300 P0106 P0506
Involved Region or Country North America
Condition
A Vehicle may have a concern of service engine light, misfire and engine noise with possible of DTC P0300 P0106 P0506.
Cause
Possible broken valve spring.
CorrectionDuring inspection if you determine that the engine has a broken valve spring it will be necessary to perform a cylinder leakage test on the affected cylinder.
If no cylinder leakage is observed it will be necessary to replace all valve springs on both banks if the vehicle is built between June 1, 2020 to September 15, 2020. Note: This only applies to the 6.2L engines RPOs L87, LT1, LT4 and LT2. For all other engine RPOs L82, L84 and L8T just replace the affected valve spring.
If you determine that engine has cylinder leakage it will be necessary to inspect further to determine the extent of the engine damage to determine correct repair required.
Important: All valve springs will be requested back for further analysis and inspection.
Subject: Service Engine Light misfire engine noise With DTC P0300 P0106 P0506
Involved Region or Country North America
Condition
A Vehicle may have a concern of service engine light, misfire and engine noise with possible of DTC P0300 P0106 P0506.
Cause
Possible broken valve spring.
CorrectionDuring inspection if you determine that the engine has a broken valve spring it will be necessary to perform a cylinder leakage test on the affected cylinder.
If no cylinder leakage is observed it will be necessary to replace all valve springs on both banks if the vehicle is built between June 1, 2020 to September 15, 2020. Note: This only applies to the 6.2L engines RPOs L87, LT1, LT4 and LT2. For all other engine RPOs L82, L84 and L8T just replace the affected valve spring.
If you determine that engine has cylinder leakage it will be necessary to inspect further to determine the extent of the engine damage to determine correct repair required.
Important: All valve springs will be requested back for further analysis and inspection.
Last edited by Newdude; Sep 23, 2020 at 09:09 AM.
Popular Reply
Sep 23, 2020, 10:47 AM
Team Owner
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Valve spring failures are generally cases of infant mortality or old age. Infant mortality is the result of manufacturing defects either related to casting or spring hardening, which involves a precise process of cooling the spring after casting at an appropriate rate.
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Additional bad news. My friend's C8 with about 52 miles started misfiring last night and shut down. He gave up on waiting for the wrecker that onstar sent. He finally got a ride and picked up his truck and trailer and picked it up himself. Just got to dealer this morning and it has misfire codes.
My C8 was built July 22 and I have 1100 miles on it and so far no problems.
My C8 was built July 22 and I have 1100 miles on it and so far no problems.
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Instructor
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From: Woodstock GA
For the first time I am glad my TPW got pushed from September to October so I won't have to worry about this!
The good news is that GM found the problem and it is a "relatively" simple fix to replace the springs. Don't have to drop the engine!
Other good news is that it is not a design problem and not an engine manufacturing problem. Just a simple supplier problem that made a bad batch of springs. Could happen to any car/engine. I am just relieved that they have identified the problem and the fix.
The good news is that GM found the problem and it is a "relatively" simple fix to replace the springs. Don't have to drop the engine!
Other good news is that it is not a design problem and not an engine manufacturing problem. Just a simple supplier problem that made a bad batch of springs. Could happen to any car/engine. I am just relieved that they have identified the problem and the fix.
Last edited by mcooper; Sep 23, 2020 at 10:03 AM.
Burning Brakes
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The TSB says VEHICLES built between 6 1 20 and 9 15 20.
I would hope GM would not be installing engines that were built during the period of concern but i have VERY LITTLE faith in GM QI process.
From past experience with GM they will just keep installing the engine regardless of build date and hope for the best.
I think another delay on C8 builds is something GM won't allow to happen .
With that said I hope I am wrong but prior experience on my 2016 Callaway SC 757 which had the rear diff replaced at 107 miles and the entire engine and torque tube replaced at 700 miles has me questions GM QI control.
I also had my 2007 Z06 needed a clutch replacement at less than 1000 miles.
Fortunately my 14 stingray and 15 z06 where problem free.
I am hoping for the best on the 2020 HTC.
If I was using the Corvette for anything other than weekend toys I would never tolerate the pics poor GM QI process.
Fortunately I can deal with the issue as I have other toys to drive when my brand new Corvette have to go in for serious warranty issue on brand new vehicles.
Been a Corvette guy my whole life so maybe I am a gluten for punishment?
Seem the Corvette team has more QI issue than other models of Chevrolet.
I have purchased 3 new Silverado High Country's and driven them thousands of miles and never had 1 issue.
Great trucks and I would recommend them to anyone !!
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From: Central Illinois
Race Director
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From: Central Illinois
Not how it works, the spring doesn't split in half vertically and fall away, the coil breaks and everything is still captured. None have tagged a piston yet because of this. It can be changed from above without dropping the motor. I did it myself on my 76 Corvette to replace valve seals back in 1983, it's not that big of a deal to change the springs.
Team Owner
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Valve spring failures are generally cases of infant mortality or old age. Infant mortality is the result of manufacturing defects either related to casting or spring hardening, which involves a precise process of cooling the spring after casting at an appropriate rate.
Advanced
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Not how it works, the spring doesn't split in half vertically and fall away, the coil breaks and everything is still captured. None have tagged a piston yet because of this. It can be changed from above without dropping the motor. I did it myself on my 76 Corvette to replace valve seals back in 1983, it's not that big of a deal to change the springs.
But if you're unaware it's broken and you bring the RPM's up, wouldn't you get valve float and piston to valve contact?
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From: Garden Valley CA
I haven't kept up with the technology lately but valve springs (and all other automotive coil springs) used to be made of drawn wire, not castings. Has that changed?
