[Z06] GM response to LS7 valve guide issue summary confirmed
10-17-2012, 08:14 PM
#1001
Team Owner
This is what I said who knows how many pages ago....
A dealer will NOT check your heads without a TSB from GM stating they will be compensated for the labor to check.
If you want your heads checked, at least at this stage in the game, it will be on your dime if they don't find wear. If they do it will be covered if your under warranty.
This is the disclaimer you will get from any dealer.
A dealer will NOT check your heads without a TSB from GM stating they will be compensated for the labor to check.
If you want your heads checked, at least at this stage in the game, it will be on your dime if they don't find wear. If they do it will be covered if your under warranty.
This is the disclaimer you will get from any dealer.
We certainly are not at the point where dealers will be removing heads because we ask them too.
DH
10-17-2012, 08:15 PM
#1002
This is what I said who knows how many pages ago....
A dealer will NOT check your heads without a TSB from GM stating they will be compensated for the labor to check.
If you want your heads checked, at least at this stage in the game, it will be on your dime if they don't find wear. If they do it will be covered if your under warranty.
This is the disclaimer you will get from any dealer.
A dealer will NOT check your heads without a TSB from GM stating they will be compensated for the labor to check.
If you want your heads checked, at least at this stage in the game, it will be on your dime if they don't find wear. If they do it will be covered if your under warranty.
This is the disclaimer you will get from any dealer.
Now if there was a bulletin on this issue...this service call may or may not played out a little differently. At this point in time I am sitting waiting patiently...however this "noise" to listen for i believe is bullchit...many pros I have talked to said this guide wear wont be a audible noise that will be obvious to anyone...especially a dealer mechanic who thinks your just being a worry wart about your precious little corvette. Now if someone could provide me the bulletin# that most likely exists linking a noise to engine failure in the valve train...well at least i could do the dealerships job for them and help them look it up.
10-17-2012, 08:19 PM
#1003
Race Director
The problem is they don't know which heads, got the bad guides.
If they knew that, then they'd know, or at least have an idea of which engines got the bad heads. http://forums.corvetteforum.com/c6-z...post1562202716
If they knew which engines got the bad heads, they'd know which cars got the "at risk" engines, and they could issue a VIN list and replace the heads.
I posted the following 10/09/07, over 5 years ago:
They know which cylinder heads are on which engine blocks. They know which engine blocks are in which cars......but what they don't know is which guides are in which heads.
And this is the reason why there is no VIN range.
This whole affair, has to be a nightmare for them.
You give them an engine number, or a VIN number, and they can tell you what this EUN sticker on the cylinder head reads. They can read it back to you, and tell you which engine block it sits on, ..or at least sat on, when it left Wixom.
But what they can't tell you, is if any of the bad guides which were produced, are in that head.
Unless the heads were delivered in lots, and they have collated data on the failed heads they have collected as to which lot was milled incorrectly, it will be nearly impossible for GM to point to specific VINs or built blocks 
. If the milling error occurred sporadically, it'll be a needle in a haystack situation. We'll have wait and see what they produce as a way to address the issue. and this also might be why we have not heard much from GM , they are stuck .. As quick said its a nightmare for them and Turning out to be for us too IMO This is what I said who knows how many pages ago....
A dealer will NOT check your heads without a TSB from GM stating they will be compensated for the labor to check.
If you want your heads checked, at least at this stage in the game, it will be on your dime if they don't find wear. If they do it will be covered if your under warranty.
This is the disclaimer you will get from any dealer.
A dealer will NOT check your heads without a TSB from GM stating they will be compensated for the labor to check.
If you want your heads checked, at least at this stage in the game, it will be on your dime if they don't find wear. If they do it will be covered if your under warranty.
This is the disclaimer you will get from any dealer.
so far they are treating this the same they would any other problem in any car . I'm afraid this is the best we are going to get out of all this , that and maybe if we're lucky additional info somehow on range of Engines .. 
10-17-2012, 08:23 PM
#1004
Team Owner
10-17-2012, 08:37 PM
#1005
Melting Slicks
Take your car into the dealer and tell them you are concerned about your heads/motor. Tell them GM Cust Service advised you to do this. If your car is under warranty I believe they will at least look at it and then send you on your way if they don't hear anything suspicious. You have at least got your self into the computer system. If they refuse to do anything then report back to GM Cust Service. They are advising everyone to get back to them if they have further issues.
We certainly are not at the point where dealers will be removing heads because we ask them too.
DH
We certainly are not at the point where dealers will be removing heads because we ask them too.
DH
I did exactly this. I printed out Evans message and went to the dealer. They looked over the car and said it wasn't making any abnormal sounds and sent me on my way. I am still under warranty however.
I was told even under warranty I would have to out of pocket to have them visually inspected if it turned out after inspection that there were no problems.
Last edited by propain; 10-17-2012 at 08:40 PM.
10-17-2012, 08:44 PM
#1006
Melting Slicks
I am seriously starting to question the fixed as of Feb 11 date, because there is a May 11 build with guide wear here.
http://forums.corvetteforum.com/c6-z...post1582103568
http://forums.corvetteforum.com/c6-z...post1582103568
10-17-2012, 08:52 PM
#1007
Melting Slicks
That's not bad at all.
That's because it's an obvious lie in my opinion. Every guide has the potential to be bad.
So GM reps, what say you to this? Problem contained yet a brand new 4500 mile car has worn guides out of your time frame.
I'm going to start documenting all these posts for future legal action.
I am seriously starting to question the fixed as of Feb 11 date, because there is a May 11 build with guide wear here.
http://forums.corvetteforum.com/c6-z...post1582103568
http://forums.corvetteforum.com/c6-z...post1582103568
So GM reps, what say you to this? Problem contained yet a brand new 4500 mile car has worn guides out of your time frame.
I'm going to start documenting all these posts for future legal action.
Last edited by gatti-man; 10-17-2012 at 09:12 PM.
10-17-2012, 09:27 PM
#1008
I would be very curious on how they would be checking them....the quickest way is to remove valve covers..take out spark plugs and inject the cylinder with air pressure to hold the valve in place...then remove rocker arms...and measure the clearances...if you repeated this process on 16 valves I would think it would take a minimum a few hours or more. $200 seems awful cheap to do all that...and I would do it in a heartbeat...if you look in another thread recently started this method was used to find a failure in a low mileage 11 MY.
10-17-2012, 09:28 PM
#1009
That's not bad at all.
That's because it's an obvious lie in my opinion. Every guide has the potential to be bad.
So GM reps, what say you to this? Problem contained yet a brand new 4500 mile car has worn guides out of your time frame.
I'm going to start documenting all these posts for future legal action.
That's because it's an obvious lie in my opinion. Every guide has the potential to be bad.
So GM reps, what say you to this? Problem contained yet a brand new 4500 mile car has worn guides out of your time frame.
I'm going to start documenting all these posts for future legal action.
But I am glad that Bill decided, after thinking long and hard about whether or not to go forward with this information, to in fact go ahead and post his information up.
But when he says how much mileage he has on that car, I don't believe it's "wear".
10-17-2012, 09:33 PM
#1010
Melting Slicks
I don't believe it's "wear".
But I am glad that Bill decided, after thinking long and hard about whether or not to go forward with this information, to in fact go ahead and post his information up.
But when he says how much mileage he has on that car, I don't believe it's "wear".
But I am glad that Bill decided, after thinking long and hard about whether or not to go forward with this information, to in fact go ahead and post his information up.
But when he says how much mileage he has on that car, I don't believe it's "wear".
10-17-2012, 09:42 PM
#1011
This first case, a car with 4K miles on it, was the actual turning point for me.
1. Many of the cars are rarely driven. Garage queens. One guy a few posts up mentions only about 700 miles a year on his.
2. Of the ones which are driven, many are not tracked. An environment where failures are most likely to manifest. Highway miles are possibly considerably less likely to result in an engine failure than say, 15 or more, track days. The bulk of these 27,000 plus cars, are probably not going to see much road course duty.
3. The failures which do occur on the track, are easily, and often times very rapidly, attributed to "missed shifts" and user error, and are frequently dismissed as such. Also in many cases of broken valves, guide wear was likely never even checked for by anyone, after the catastrophe, and either a new engine put into the car under warranty, or on the owner's dime.
With regard to #3 consider this:
A Z06 comes into a dealership with a popped LS7, the first thing they check is not going to be the valve guides.
The first thing they are going to check, is the ECM.
So if the valve guides were worn, it is quite possible that no one will ever know.
Last edited by '06 Quicksilver Z06; 10-17-2012 at 10:01 PM.
10-17-2012, 10:59 PM
#1012
Team Owner
I did exactly this. I printed out Evans message and went to the dealer. They looked over the car and said it wasn't making any abnormal sounds and sent me on my way. I am still under warranty however.
I was told even under warranty I would have to out of pocket to have them visually inspected if it turned out after inspection that there were no problems.
I was told even under warranty I would have to out of pocket to have them visually inspected if it turned out after inspection that there were no problems.
DH
10-17-2012, 11:03 PM
#1013
Team Owner
I am seriously starting to question the fixed as of Feb 11 date, because there is a May 11 build with guide wear here.
http://forums.corvetteforum.com/c6-z...post1582103568
http://forums.corvetteforum.com/c6-z...post1582103568
DH
10-17-2012, 11:09 PM
#1014
Team Owner
10-17-2012, 11:11 PM
#1015
Did GM replace it for him?
10-17-2012, 11:17 PM
#1016
Pro
This is what I receieved from customer service below...
JT,
My name is Tricia and I am assisting Evan while he is out of the office. We do not have specifics on build dates or VINs affected at this time other than knowing that the concern was contained as of the Feb 2011. If you are experiencing a concern, I would recommend contacting your local dealer for a diagnosis. If and when more information becomes available, either Evan or I will be sure to pass it along. You can also contact me if you have any additional question or need assistance.
Tricia, Chevrolet Customer Service.
JT,
My name is Tricia and I am assisting Evan while he is out of the office. We do not have specifics on build dates or VINs affected at this time other than knowing that the concern was contained as of the Feb 2011. If you are experiencing a concern, I would recommend contacting your local dealer for a diagnosis. If and when more information becomes available, either Evan or I will be sure to pass it along. You can also contact me if you have any additional question or need assistance.
Tricia, Chevrolet Customer Service.
10-17-2012, 11:20 PM
#1017
Team Owner
DH
10-17-2012, 11:24 PM
#1018
Instructor
Bill's is actually the second case that I have read about in here which were out of spec in about 4K miles.
This first case, a car with 4K miles on it, was the actual turning point for me.
http://forums.corvetteforum.com/c6-z...post1581557233
Actually, if you think about it, it becomes a little "easier" to understand.
1. Many of the cars are rarely driven. Garage queens. One guy a few posts up mentions only about 700 miles a year on his.
2. Of the ones which are driven, many are not tracked. An environment where failures are most likely to manifest. Highway miles are possibly considerably less likely to result in an engine failure than say, 15 or more, track days. The bulk of these 27,000 plus cars, are probably not going to see much road course duty.
3. The failures which do occur on the track, are easily, and often times very rapidly, attributed to "missed shifts" and user error, and are frequently dismissed as such. Also in many cases of broken valves, guide wear was likely never even checked for by anyone, after the catastrophe, and either a new engine put into the car under warranty, or on the owner's dime.
With regard to #3 consider this:
A Z06 comes into a dealership with a popped LS7, the first thing they check is not going to be the valve guides.
The first thing they are going to check, is the ECM.
So if the valve guides were worn, it is quite possible that no one will ever know.
This first case, a car with 4K miles on it, was the actual turning point for me.
http://forums.corvetteforum.com/c6-z...post1581557233
Actually, if you think about it, it becomes a little "easier" to understand.
1. Many of the cars are rarely driven. Garage queens. One guy a few posts up mentions only about 700 miles a year on his.
2. Of the ones which are driven, many are not tracked. An environment where failures are most likely to manifest. Highway miles are possibly considerably less likely to result in an engine failure than say, 15 or more, track days. The bulk of these 27,000 plus cars, are probably not going to see much road course duty.
3. The failures which do occur on the track, are easily, and often times very rapidly, attributed to "missed shifts" and user error, and are frequently dismissed as such. Also in many cases of broken valves, guide wear was likely never even checked for by anyone, after the catastrophe, and either a new engine put into the car under warranty, or on the owner's dime.
With regard to #3 consider this:
A Z06 comes into a dealership with a popped LS7, the first thing they check is not going to be the valve guides.
The first thing they are going to check, is the ECM.
So if the valve guides were worn, it is quite possible that no one will ever know.
I think there is quite a bit of validity in GMs statementment that it was a machining issue with the guides at the factory. What people were thinking was extreme guide wear already had a big start when the cars left the factory.
10-17-2012, 11:26 PM
#1019
I got a response too that is similar to what others have received. Mine was more regarding the 2008 cars that are about to be out of warranty, and fall under this machining error that they claim. The bold part was what interests me.
My name is Tricia and I am assisting Evan while he is out of the office. We do not have information at this time on specific VINs. We would be willing to take a look at each customer who feels that they are experiencing this concern. We can set up a case for them and work with them as long as they are working with a GM dealer. We can not guarantee assistance, but we can look at this on a case by case basis even for those out of warranty. would have to recommend that you contact your local GM dealer to have them take a look if you feel that you are experiencing a concern. Let me know if you would like additional assistance. Either Evan or I will be sure to pass along any additional information if and when it becomes available. Thank you.
Tricia, Chevrolet Customer Service.
Tricia, Chevrolet Customer Service.
10-17-2012, 11:28 PM
#1020
Ricky, take a look at post 222 by beden1, his situation is very similiar to mine. http://forums.corvetteforum.com/c6-z...-valve-12.html although they replaced his parts not the whole head. There is also this thread on the ZR1 forum with that car only having 1300 miles http://forums.corvetteforum.com/c6-z...-valve-12.html
I think there is quite a bit of validity in GMs statementment that it was a machining issue with the guides at the factory. What people were thinking was extreme guide wear already had a big start when the cars left the factory.
I think there is quite a bit of validity in GMs statementment that it was a machining issue with the guides at the factory. What people were thinking was extreme guide wear already had a big start when the cars left the factory.
Yes, I see what you mean. I read the post by beden1.