[Z06] GM response to LS7 valve guide issue summary confirmed
09-01-2012, 12:11 AM
#41
"GM discovered the problem through their cylinder head warranty data; it went from nearly 0 to a peak of 6.5 problems per thousand engines."
So before 2009 there have been no problems with dropped valves? Really?
"If a car makes it through even a fraction of the 100k mile warranty, it is built properly and will have a complete service life."
Define fraction 10%, 20% or is it 50%. There are cars with low miles dropping valves including 06' through 08's. I am having a hard time believing this.
So before 2009 there have been no problems with dropped valves? Really?
"If a car makes it through even a fraction of the 100k mile warranty, it is built properly and will have a complete service life."
Define fraction 10%, 20% or is it 50%. There are cars with low miles dropping valves including 06' through 08's. I am having a hard time believing this.
This thread/topic/statement covers the milling issue found affecting a small number of 2009-11 cars.
The other issue, the guide wear, is not addressed in this thread/topic/statement and is the cause of the other failures for all MYs.
09-01-2012, 12:15 AM
#42
Melting Slicks
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If it helps, the way I've understood the problem is that there is a single issue (valves dropping) with two root causes (guides & milling).
This thread/topic/statement covers the milling issue found affecting a small number of 2009-11 cars.
The other issue, the guide wear, is not addressed in this thread/topic/statement and is the cause of the other failures for all MYs.
This thread/topic/statement covers the milling issue found affecting a small number of 2009-11 cars.
The other issue, the guide wear, is not addressed in this thread/topic/statement and is the cause of the other failures for all MYs.
09-01-2012, 12:22 AM
#43
Safety Car
09-01-2012, 12:27 AM
#44
The language makes it a little ambiguous, but I'm lead to believe the 0 to 6.5 per thousand is the number of issues related the cylinder head (which is the part affected by the milling problem) and perhaps not necessarily all of the components one would find in it, like the valves. This is sort of addressed in an earlier point.
"It sounds like it's affecting a reasonably small number of '09, '10, and '11 Z06s. It's not the cause of any issues that have popped up with the LS7 in prior MYs."
This point states that the milling issue is a different root cause than any of the other causes found in failures for other cars. This is what leads me to believe they're only referring to the milling issue in this statement while acknowledging, but not addressing/commenting on the guide wear issue.
"It sounds like it's affecting a reasonably small number of '09, '10, and '11 Z06s. It's not the cause of any issues that have popped up with the LS7 in prior MYs."
This point states that the milling issue is a different root cause than any of the other causes found in failures for other cars. This is what leads me to believe they're only referring to the milling issue in this statement while acknowledging, but not addressing/commenting on the guide wear issue.
09-01-2012, 12:29 AM
#45
Melting Slicks
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Well maybe he should have written that then. Still leaves GM with no postiion on the 06 to 08 valve failures and there are a few of them. I for one would like to here something about that.
09-01-2012, 12:50 AM
#47
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The language makes it a little ambiguous, but I'm lead to believe the 0 to 6.5 per thousand is the number of issues related the cylinder head (which is the part affected by the milling problem) and perhaps not necessarily all of the components one would find in it, like the valves. This is sort of addressed in an earlier point.
"It sounds like it's affecting a reasonably small number of '09, '10, and '11 Z06s. It's not the cause of any issues that have popped up with the LS7 in prior MYs."
This point states that the milling issue is a different root cause than any of the other causes found in failures for other cars. This is what leads me to believe they're only referring to the milling issue in this statement while acknowledging, but not addressing/commenting on the guide wear issue.
"It sounds like it's affecting a reasonably small number of '09, '10, and '11 Z06s. It's not the cause of any issues that have popped up with the LS7 in prior MYs."
This point states that the milling issue is a different root cause than any of the other causes found in failures for other cars. This is what leads me to believe they're only referring to the milling issue in this statement while acknowledging, but not addressing/commenting on the guide wear issue.
09-01-2012, 01:01 AM
#49
Fine, so there is a root cause for the 09 plus issues, that from the data on the forum is seen at a lower rate than the failures seen in the 06 to 08 MY's. It seems to me that GM owes the 06 to 08 owners the due diligence on these failures as well or maybe they don't care as the cars are out of warranty or soon will be. Here is the bottom line from my point of view. I own an 08 and it will be out of warranty 8/2013. I hope it pukes a valve before then so GM can give me a new motor that doesn't have an issue aka 09 or newer and that is a joke too. Beyond this they can kiss my ***, I paid a lot of money for a car that everytime I hit the start button I have to wonder if the motor is going to pop. Thanks a freaking bunch for that. My car is unofficially for sale. I am going to move on as the pleasure of driving it is not worth the stress of worrying about a catastrophic motor failure.
09-01-2012, 01:23 AM
#50
Racer
So, now that GM has documented these issues would it be safe to assume that later 2011's, 12's and 13's have addressed all the known issues and are therefore bulletproof?
09-01-2012, 01:36 AM
#51
Team Owner
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St. Jude Donor '06
But it would seem the later build cars you reference do not have this QC issue referenced in this thread.
Great thread Mike, to bad however there is no explanation yet in this thread why there have been more than a normal amount of excessive valve guide ware and dropped exhaust valves in 2006, 07 and 08 model year Zs, but it looks like Jason's from Katechs post on the other thread is moving us torwards the right direct on the older model Zs, and would love to see what is going to be said in GM's statement that Katech states is coming soon on this issue.
Last edited by Mopar Jimmy; 09-01-2012 at 01:47 AM.
1000%, making Jason from Katech's comments made today on the LS7 valve dropping issue is a must for a sticky!!!!!!!!!
09-01-2012, 02:39 AM
#53
As far as I can tell, this just tells us that the 06-08 and late 2011-13s aren't affected by the milling issue.
09-01-2012, 11:03 AM
#55
Melting Slicks
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I intend to keep driving it while I have the warranty. Meanwhile I will keep my ears open and maybe GM will figure out why the 06 to 08's have an issue. I know if I decide to keep it beyond the warranty the heads are coming off and getting upgraded to ensure future reliability.
09-01-2012, 11:35 AM
#56
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I'm just going to point this out:
http://forums.corvetteforum.com/c6-z...erring-to.html
This is from 2005. GM must've known about the dropped valves for the last 7 years...? Perhaps they thought they resolved the issue way back when?
Here is the quote from that 7 year old thread, which I linked above:
http://forums.corvetteforum.com/c6-z...erring-to.html
This is from 2005. GM must've known about the dropped valves for the last 7 years...? Perhaps they thought they resolved the issue way back when?
Here is the quote from that 7 year old thread, which I linked above:
Originally Posted by CHRISPY
Several motors have dropped valves. They are running lash caps on the intake valves as the stock titanium intake valves do not have steel tips.
(There are no lash caps on the exhaust valves)
Why they would put a lash cap and a non steel tipped titanium valve on a motor like this I have no idea (supply issues?)
(There are no lash caps on the exhaust valves)
Why they would put a lash cap and a non steel tipped titanium valve on a motor like this I have no idea (supply issues?)
Last edited by Black96WS6; 09-01-2012 at 11:37 AM.
09-01-2012, 11:35 AM
#57
Racer
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My thoughts exactly. It sounds likes there's two separate issues; bad milling on 09 and up and premature guide wear on all model years. Mine's modded so for me it doesn't matter if GM goes to bat for the 06-08 Z owners. But I hope they do the right thing for the rest of my fellow Z owners. Time will tell.
09-01-2012, 11:54 AM
#58
Safety Car
My thoughts exactly. It sounds likes there's two separate issues; bad milling on 09 and up and premature guide wear on all model years. Mine's modded so for me it doesn't matter if GM goes to bat for the 06-08 Z owners. But I hope they do the right thing for the rest of my fellow Z owners. Time will tell.
A lot of these early owners paid over sticker price for the z06. If there was a QC issue those owners should have this problem fixed too.
It does not matter to me since I'm going to take of the issue myself next week but for owners who keep there car stock something should be done.
09-01-2012, 12:29 PM
#59
Le Mans Master
Strategic words to keep them out of fault, I would venture to say most failures would be from 2006-2008, conveniently now out of warranty, the problem exists in ALL LS7's regardless off year , gm knows this, hence the rep stating the later cars being a problem.
Typical government action
Seriously does government motors think we are that dumb ?
09-01-2012, 12:33 PM
#60
That is why it is unofficially for sale. I do really enjoy driving the car, but the thought is always there in the back of my head, maybe today is the day it goes. I intend to keep driving it while I have the warranty. Meanwhile I will keep my ears open and maybe GM will figure out why the 06 to 08's have an issue. I know if I decide to keep it beyond the warranty the heads are coming off and getting upgraded to ensure future reliability.
I intend to keep driving it while I have the warranty. Meanwhile I will keep my ears open and maybe GM will figure out why the 06 to 08's have an issue. I know if I decide to keep it beyond the warranty the heads are coming off and getting upgraded to ensure future reliability.You address that which you think, (and that is going to vary from one owner to the next, what they think) is the culprit in these failures and go from there.
There comes a time to stop arguin', fussin', cussin' and belly achin' about it and DO something.
I'm not talking about you personally achilds, but for some of us, it's time for all of this talking' to end. Don't talk......DO.
Either sell it, extend the warranty on it, or fix that which you think is wrong with it. And for those who think that there is nothing wrong with it, keep driving.
For those who thnk that GM *****d you, OK well, GM *****d you.........What are you going to DO?
Enough talk, what are you going to DO?
Last edited by '06 Quicksilver Z06; 09-01-2012 at 12:36 PM.