Notices
C6 Corvette ZR1 & Z06 General info about GMs Corvette Supercar, LS9 Corvette Technical Info, Performance Upgrades, Suspension Setup for Street or Track Advertisement

[Z06] GMEPP and LS7 heads

 
Old 01-07-2017, 01:03 PM
  #1  
golfinz
CF Senior Member
Thread Starter
 
golfinz's Avatar
 
Member Since: Jul 2007
Location: Austin TX
Posts: 2,087
Liked 10 Times in 10 Posts
Default GMEPP and LS7 heads

I've searched for what feels like a few days but can't seem to find an answer.

A little background, I am considering the purchase of a 2009 Z06 from the original owner (cyber gray, 2lt 30k miles, all stock, mint) but of course am worried about the heads. The owner has never heard of this forum or was aware of any issue with the heads/valves so he didn't have them addressed. Despite this, I think I'm getting a pretty good price on the car (37k).

If anyone of you have been on the C5Z side, you might recognize my forum name. I've owned three different c5z's, ranging from cam only to full 402/novi2k build making 900rwhp. This time around, I want to keep the car stock. Because of this, I'm looking at getting the "new" GMEPP warranty (aka the Chevy Protection Plan). A 3 year/30k warranty is about the same price as fixing the heads with something like the AHP heads.

I've read about the old GMPP warranty, and there seemed to be a lot of success getting the heads repaired under that plan. But since that isn't around, does anyone have experience with the GMEPP (Chevy Protection Plan), specifically repairing the heads, or if a valve dropped, getting a new motor?

I'm excited about this car, but also a little "hesitant" because of this. The other car I'm considering is an ATS-V

edit: I know a warranty isn't a sure thing and the car could sit at the Chebby dealer for a while if they deny a repair/fix, but it seems to offer some comfort. As does a set of new heads.

Last edited by golfinz; 01-07-2017 at 01:37 PM.
golfinz is offline  
Old 01-07-2017, 02:38 PM
  #2  
Hib Halverson
CF Senior Member
 
Member Since: Oct 1999
Location: Goleta CA
Posts: 2,021
Liked 146 Times in 94 Posts
Default

Does the car you're considering buying already have the GM extended warranty and you're asking if it is transferrable?

Or are you asking: if you buy a used Z06 can you buy a GM extended warranty for it?

Also if it were me and I was weighing buying an extended warranty vs. having the existing heads done by Katech, West Coast Cylinder Heads or Texas Speed, I'd go with the second choice.

If you're interested in an ATS-V, take a look at "A Little V-Blog" over on the V-Net.

Last edited by Hib Halverson; 01-07-2017 at 02:40 PM.
Hib Halverson is offline  
Old 01-07-2017, 03:02 PM
  #3  
golfinz
CF Senior Member
Thread Starter
 
golfinz's Avatar
 
Member Since: Jul 2007
Location: Austin TX
Posts: 2,087
Liked 10 Times in 10 Posts
Default

Hib, thanks. The car does not have a warranty and am considering the GMEPP, the platinum version.

Regarding warranty vs fix heads, both are about 3k, including install and tune with the heads. If I decide to go with the warranty, I'm wanting to get some first hand experience from guys that have it and have used it specifically for the heads/valves.

I know people can't make the decision for me, so I'm trying not to ask the "heads vs warranty" question, rather I wanted to see if anyone picked the warranty route and if they had valve issues, did the GMEPP cover the costs. If the GMEPP does really cover everything it says it does, then it seems like a great alternative to replacing the heads.

RE atsv, I'm on the cadillacforum and see that you contribute there a lot as well. Thanks for your time on that board and on your linked thread as well. Very helpful!

Last edited by golfinz; 01-07-2017 at 03:10 PM.
golfinz is offline  
Old 01-07-2017, 04:58 PM
  #4  
Bill Dearborn
Tech Contributor
 
Bill Dearborn's Avatar
 
Member Since: Oct 1999
Location: Charlotte (formerly Endicott, NY) NC
Posts: 33,030
Liked 3,485 Times in 2,327 Posts
Default

The problem with valves dropping isn't necessarily an ubiquitous one but it does happen often enough to cause concern. If it didn't have potential disastrous consequences from a financial let alone personal danger standpoint it might not occur often enough to worry about until it actually happens. However, due to the consequences you do need to have a plan on how you are going to address a potential problem.

I would suggest a different plan than you have now. The first thing to do is if you want the car then buy the car. Then if you can get a GMEPP warranty consider it for the cost/duration and what ever kinds of repairs you might expect.

Subsequent to your decision on the warranty then have the heads removed and checked at a competent machine shop that will check the guides with a valve guide bore gauge and the valve stems with a micrometer. Aftermarket warranties (including GMPP) don't authorize people to go hunting for problems that aren't observable so don't ask them to pay for it ahead of time.

If the heads are in good shape all you need do is pay for the removal, disassembly, checking, reassembly and reinstallation. When I had my heads checked I pre negotiated that price (including applicable materials) and knew going in what my minimal cost ($1400) was going to be.

However, if the heads prove to have guide clearances or other problems that are out of tolerance from a GM service spec standpoint then you can make your plans on how to proceed. With two intake guides out of tolerance that is where I ended up. That is when I had the shop call GMPP to see if they would cover the repair (I actually had an observable issue). They said they would and provided coverage for removal of the old heads and installation of two new heads. From there I had the two new heads modified so they would stand up to track duty. Appropriate bronze guides and Ti/Mo Intake and Exhaust valves. Everything else was left stock. Total out of pocket cost to me was $2800 for the guides, valves (16 at $160 ea) and the machine shop labor. That was further deferred by the shop giving me $1000 for my old heads.

No matter which C6Z you purchase you have to wonder about valve drops. Some may have been fixed but you still need to worry about it since unless you had it done by somebody that you trust there is no way to know for sure about the fix. No way you can get around that.

Bill
Bill Dearborn is offline  
The following users liked this post: Bill Dearborn
golfinz (01-08-2017)
Old 01-08-2017, 12:49 PM
  #5  
Landru
CF Senior Member
 
Landru's Avatar
 
Member Since: Dec 2002
Location: Wayne Township WI
Posts: 8,570
Liked 412 Times in 366 Posts
Default

I've an '08 w/ 54K, bought new first owner.
Following B2B expiration have had 2 GMPPs, second last I qualified for. I understood absent warranty protection heads had to be done. Period. So was thinking heads all the way.

Then GMEPP was introduced in '16 & I qualified.
Like you found cost for quality heads w/ labor was slightly more than GMEPP coverage.
Since up to now car's been perfect, decided on GMEPP and now covered 'til '19 or 80K.
BUT...it'd been one or the other.

Now IF a catastrophic failure occurs a brand new LS7 will be installed including labor per contract, providing vehicle's factory stock & after confirmation by GMEPP's rep.

GMEPP actually has better coverage than old GMPP, things like mag shocks etc are now covered whereas before they weren't.
Good deal for many owners since C6 systems are not cheap to make right when they go south w/ diagnostic $ to the moon.

If you get GMEPP coverage just leave drivetrain alone and simply enjoy w/o angst or concern a $20K gobln's waiting to pounce.
Landru is offline  
Old 01-08-2017, 12:57 PM
  #6  
golfinz
CF Senior Member
Thread Starter
 
golfinz's Avatar
 
Member Since: Jul 2007
Location: Austin TX
Posts: 2,087
Liked 10 Times in 10 Posts
Default

Originally Posted by Bill Dearborn View Post
The problem with valves dropping isn't necessarily an ubiquitous one but it does happen often enough to cause concern. If it didn't have potential disastrous consequences from a financial let alone personal danger standpoint it might not occur often enough to worry about until it actually happens. However, due to the consequences you do need to have a plan on how you are going to address a potential problem.

I would suggest a different plan than you have now. The first thing to do is if you want the car then buy the car. Then if you can get a GMEPP warranty consider it for the cost/duration and what ever kinds of repairs you might expect.

Subsequent to your decision on the warranty then have the heads removed and checked at a competent machine shop that will check the guides with a valve guide bore gauge and the valve stems with a micrometer. Aftermarket warranties (including GMPP) don't authorize people to go hunting for problems that aren't observable so don't ask them to pay for it ahead of time.

If the heads are in good shape all you need do is pay for the removal, disassembly, checking, reassembly and reinstallation. When I had my heads checked I pre negotiated that price (including applicable materials) and knew going in what my minimal cost ($1400) was going to be.

However, if the heads prove to have guide clearances or other problems that are out of tolerance from a GM service spec standpoint then you can make your plans on how to proceed. With two intake guides out of tolerance that is where I ended up. That is when I had the shop call GMPP to see if they would cover the repair (I actually had an observable issue). They said they would and provided coverage for removal of the old heads and installation of two new heads. From there I had the two new heads modified so they would stand up to track duty. Appropriate bronze guides and Ti/Mo Intake and Exhaust valves. Everything else was left stock. Total out of pocket cost to me was $2800 for the guides, valves (16 at $160 ea) and the machine shop labor. That was further deferred by the shop giving me $1000 for my old heads.

No matter which C6Z you purchase you have to wonder about valve drops. Some may have been fixed but you still need to worry about it since unless you had it done by somebody that you trust there is no way to know for sure about the fix. No way you can get around that.

Bill
Thank you Bill! Does GMPP, or GMEPP, work with any shop, or just GM shops? It appears that they would do with the former based on your comment. Secondly, if I paid for an inspection and something was found, could the GMEPP then be used to fix?
golfinz is offline  
Old 01-08-2017, 12:58 PM
  #7  
golfinz
CF Senior Member
Thread Starter
 
golfinz's Avatar
 
Member Since: Jul 2007
Location: Austin TX
Posts: 2,087
Liked 10 Times in 10 Posts
Default

Originally Posted by Landru View Post
I've an '08 w/ 54K, bought new first owner.
Following B2B expiration have had 2 GMPPs, second last I qualified for. I understood absent warranty protection heads had to be done. Period. So was thinking heads all the way.

Then GMEPP was introduced in '16 & I qualified.
Like you found cost for quality heads w/ labor was slightly more than GMEPP coverage.
Since up to now car's been perfect, decided on GMEPP and now covered 'til '19 or 80K.
BUT...it'd been one or the other.

Now IF a catastrophic failure occurs a brand new LS7 will be installed including labor per contract, providing vehicle's factory stock & after confirmation by GMEPP's rep.

GMEPP actually has better coverage than old GMPP, things like mag shocks etc are now covered whereas before they weren't.
Good deal for many owners since C6 systems are not cheap to make right when they go south w/ diagnostic $ to the moon.

If you get GMEPP coverage just leave drivetrain alone and simply enjoy w/o angst or concern a $20K gobln's waiting to pounce.
Great, thank you for your experience!
golfinz is offline  
Old 01-08-2017, 01:45 PM
  #8  
outhouse
CF Senior Member
 
Member Since: Jun 2016
Location: Auburn Ca
Posts: 3,882
Liked 144 Times in 130 Posts
Default

Originally Posted by golfinz View Post
I've searched for what feels like a few days but can't seem to find an answer.

A little background, I am considering the purchase of a 2009 Z06 from the original owner (cyber gray, 2lt 30k miles, all stock, mint) but of course am worried about the heads. The owner has never heard of this forum or was aware of any issue with the heads/valves so he didn't have them addressed. Despite this, I think I'm getting a pretty good price on the car (37k).

.


Knowing most unaddressed heads with your miles have guide clearance issues, just plan on having the heads done. It is cheap insurance that will provide instant results for the price of tires if you do it yourself.


Your price is OK for stock, not great and not bad.
outhouse is offline  
Old 01-08-2017, 01:53 PM
  #9  
golfinz
CF Senior Member
Thread Starter
 
golfinz's Avatar
 
Member Since: Jul 2007
Location: Austin TX
Posts: 2,087
Liked 10 Times in 10 Posts
Default

Yeah, I know I'm not getting the deal of the century, but I do value that it is a one owner car and completely stock. It is also the color I want, both inside and out.
golfinz is offline  
Old 01-08-2017, 06:19 PM
  #10  
MTPZ06
CF Senior Member
Support Corvetteforum!
 
MTPZ06's Avatar
 
Member Since: Dec 2008
Location: Honolulu HI
Posts: 12,928
Liked 1,169 Times in 1,036 Posts
Default

ATS-V's are cool little cars, but they'll be around for a while. Grab the C6Z if it's the color you want.
MTPZ06 is online now  
The following users liked this post: MTPZ06
golfinz (01-08-2017)
Old 01-08-2017, 08:47 PM
  #11  
golfinz
CF Senior Member
Thread Starter
 
golfinz's Avatar
 
Member Since: Jul 2007
Location: Austin TX
Posts: 2,087
Liked 10 Times in 10 Posts
Default

For those that had your heads repaired/replaced under the gmpp/gmepp warranty at a performance shop (ie: AHP) how did the process work when using the warranty? If I end up getting the gmepp, I would want to use a corvette performance shop vs the chebby dealer.
golfinz is offline  
Old 01-09-2017, 07:54 AM
  #12  
Undy
CF Senior Member
 
Undy's Avatar
 
Member Since: Dec 1999
Location: Virginia Beach, VA & Port Charlotte, FL (snowbird)
Posts: 3,168
Liked 90 Times in 76 Posts
Default

Originally Posted by golfinz View Post
For those that had your heads repaired/replaced under the gmpp/gmepp warranty at a performance shop (ie: AHP) how did the process work when using the warranty? If I end up getting the gmepp, I would want to use a corvette performance shop vs the chebby dealer.
The GMPP is essentially an aftermarket insurance policy offered through GM which outside (GM approved) shops can participate in. GMEPP is a warranty issued AND underwritten by GM and can ONLY be serviced through GM dealerships. If you want to go to outside performance shops you're forced to go with an outside warranty company. Be sure to do due diligence on your selection...
Undy is offline  
The following users liked this post: Undy
golfinz (01-09-2017)
Old 01-09-2017, 07:57 AM
  #13  
golfinz
CF Senior Member
Thread Starter
 
golfinz's Avatar
 
Member Since: Jul 2007
Location: Austin TX
Posts: 2,087
Liked 10 Times in 10 Posts
Default

Originally Posted by Undy View Post
The GMPP is essentially an aftermarket insurance policy offered through GM which outside (GM approved) shops can participate in. GMEPP is a warranty issued AND underwritten by GM and can ONLY be serviced through GM dealerships. If you want to go to outside performance shops you're forced to go with an outside warranty company. Be sure to do due diligence on your selection...
Perfect response, thanks Undy
golfinz is offline  

Thread Tools
Search this Thread
Quick Reply: [Z06] GMEPP and LS7 heads


Sponsored Ads
Vendor Directory

Contact Us - About Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: