Short-Throw

No, not an outsider, a GM employee.

Vette_DD

Temporarily closed at OP's request.

Will re-open with a GM rep post.

Short-Throw

Members,

GM will be posting this morning.

Please lay low until the statement is published here.

Thank you,

Mike

Chevy Cust Svc

Hello all,

LS7 Valve guide issue summary:
• Affects a small, number of '08, 09 ’10 and ’11 Z06’s
• GM discovered the condition through our cylinder head warranty data involving a very small percentage of our vehicles.
• Through inspection of returned heads, it was determined that a machining error in the valve guide had occurred at our head supplier.
• The quality issue has been contained as of Feb 2011 with 100% inspection of all heads.
• The most common customer complaint has been excessive valve train noise.
However if the condition is not addressed, it could result in engine failure. To date, where this condition has been observed, it has occurred early in the vehicle life.
What customers need to know: They should drive and enjoy their vehicles without fear. If their car demonstrates this condition, they are likely to hear unusual valvetrain noise first. If you have a concern regarding this issue on your personal vehicle feel free to contact me through private message on this forum and we will work to assist in resolving your concern. Feel free to contact me through Socialmedia@gm.com please put attention Evan in the subject. As always, vehicles that have modifications to the powertrain or the calibrations, are no longer covered by GM's warranty.

Sincerely,
Evan, Chevrolet Customer Service

erick_e

So we know what causes it, we just dont know if/when our beloved LS7 will fail.

Nothing new to see here. Move along...

forg0tmypen

What is GMs stance on excessive valve guide wear witnessed on '06 and '07 models? Can GM say with any certainty that the machining error did not affect those heads?

gatti-man

What about those who do not drive their cars daily? (Ie the majority). How will they know their engine is bad? The ls7 is a noisy motor as is. I can hear tapping in my 2011 from 1600-2200 rpm yet everyone says its normal including the dealer.

Chalky

Sorry but I am underwhelmed by the GM response. I can only assume that those with 06-07s with guide failure and/or windowed blocks were statistically insignificant.

AirBusPilot

QC issue with the supplier. Just as I suspected.

AirBusPilot

Mine has always (at least as long as I remember) made that same tapping sound in that rpm band.

32k miles on my 09'.

It would be great if GM could give a better description other than a noisy valvetrain, as these motors seem to all have valve train noise. A "noisy valvetrain" is subjective, and depends on how good your hearing is.

RFE-57

Echoing Chalky's response..............pre '08's totally clear of anomalies??????????

LFZ

They are out of warranty, therefore they are irrelevant.

propain

Is there any way to narrow down if you have a vehicle that could be affected other than listen to an already noisy valve train? That is quite a big time line.

If you have had your engine and or heads replaced recently is it safe to say that the problem is gone and even if you own a 2008-09-10? Have new long blocks been inspected or still an older batch that wasnt?

Are vehicles that are out of their current powertain warranty out of luck if the vehicle fails or will it be covered under some type of extended coverage? Your post admits fault and blame on GM's part for all those years. I cant see how GM could not accept a full warranty replacement in or out of warranty.

HyperX

Does GM plan on repairing engines on cars that are out of warranty?

Roush

Where do I sign up for the extended warranty?

HyperX

Also, is there a TSB on this yet?

gatti-man

Another question: how are the 06s and 07s not affected but the 08s are?

spicytuna

What constitutes excessive or unusual valve train noise? My 07 has been making (what I consider to be) a ticking noise since the first day I got it.

9c1ny

same questions as some others, what will GM do about warranty?
are there any specific production dates effected in regards to 2008?
As others have said LS7s seem to be noisy engines, how is one to know what is normal and what is not???????

dun4791

should we take them in to dealers and get our valve train nose documented?