ICULOOKN

Just got the car last week; it's got 8,500 miles, still got 14 months of the factory bumper-to-bumper, and remainder of drive train warranty. I'm new to the forum so forgive me if I'm posting in the wrong place but I see posts about "blown LS7 motors" and what appears to be a "known valve problems" so I'm immediately concerned and I have questions! Does the issue affect my model year? Does GM know about this and can I get it checked under warranty? If not, what should I do to protect my engine! Any advice would be very much appreciated.

Unreal

Yes your model year is affected. Keep it bone stock and under warranty, or have the heads redone with new guides/etc.

GM will fix it when the motor explodes, but until then they basically deny it exist.

ckchan10

Congratulations on your purchase! You will find A LOT of info on this subject, but here are my answers to your questions:
1. Yes it affects all years.
2. Yes GM knows about it.
3. Just drive the car as you normally would. If anything happens it will be covered under warranty.
4. When your warranty expires get your cylinder heads "fixed". There is also a lot of information on the forum regarding how. It should cost you around $2k for a reputable shop to do the work.

No need for yoy to worry since ypu are still under warranty..Enjoy your new ride and welcome!

Unreal

Only thing I would change about that is get it fixed slightly before you go out of warranty, not after.

And if you mod it, then get them fixed right away, as modding may have warranty issues.

Dan_the_C5_Man

Bingo..

ICULOOKN

Thanks to all who replied! So far I love this vette....that motor hits like nothing I've ever experienced before! It's like two entirely different cars; happy to putter around at low speeds and RPM's but when I got in the throttle (3rd gear approaching 5000k) it scared the crap outta me! I definitely don't have the skills to drive this car anywhere near its limits. I don't understand how guys are controlling these cars after adding forced induction or engine mods! I'm disappointed that I dropped this much money on a car that GM knows has issues! If I'm honest, knowing what I know now, I'd still buy the car...I like it that much. But GM should be ashamed! Thanks again to all for the help!

Todds427

Are you sure you have 14 months of warranty left? I also have a 2013 and mine expired last year, 3 yr factory warranty! I have not had ANY problems, the car runs like a dream! Don't waste your time worrying about issues you cant control, just drive it and enjoy!

ICULOOKN

That what the paper work that I got from the dealership says. I made him show me and highlight it! Got the car down in Miami...I don't know when the original owner purchased the car. Salesman says it was a local trade-in on a 2015 zo6.

Dan_the_C5_Man

Worse advice ever - anyone running without a warranty should check their guides at 10K miles, just like you should.

They ALL "run like a dream", until they don't run at all.

"Head in the sand" advice doesn't help anyone - and this issue is completely under your control.

Finally, I believe GM still offered the 5 year / 100K power train warranty for the remainder of the C6 run.

REDZED2

Warranty is great if you still have a c6 Z06 last model year but like said, won't "fix" the problem if something rears it's ugly head down the road. Otherwise these are IMO the best Z06's made for general balance of purpose built. Wasn't there as well a rod bearing issue on some 2012 -13 model year LS7's??

LMB-Z

Congrats...just keep the warranty up and if you have a problem, it should be taken care of. And go easy on the go pedal until you get used to it. Pics would be nice too.

ICULOOKN

I found the following at z06vette.com. It seems to indicate that as of 2011, GM has corrected the valve guide issue. Have any of you heard of this problem occurring on z06's produced after 2011? Would you trust this info from GM or should I consider it damage control and still have my valves fixed just prior to the warranty expiration date?


GM response to failing LS7 engines
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

AzDave47

They are great cars. If you have a good warranty and are unmodded, don't worry about it, just drive it. I bought my 09 used with 8500 miles on it. Now it has 47K, and a good number of performance events. I knew about the valve guide issue before I bought it. GM has been quite good about honoring the warranty on unmodified cars. I got an extended GMPP (now changed to GMEPP) warranty that will run out in August. I knew I wanted to get the heads fixed before that so in May I did a full HCI install with heads redone by HCCI with Katech recommended parts. Only two intake guides were within GM wear specs when my heads were checked before rebuild, all exhaust valves were out of spec (one double the limit) and the engine made no unusual noises. Usually the dealers will not check further unless there is unusual valve train noise. Also many 06 and 07 Z06 engines failed due to the same problem so GM wasn't forthright on that, either.

I believe the GMEPP warranty must be purchased before the BTB warranty runs out. Buying the additional warranty is subject to price and terms negotiation. Forum vendors and local dealers will negotiate. Do some research before you buy one and you can save $$$.

AzDave47

GM is full of BS on that. They said that they've gone to 100% inspection of heads since Feb. 2011. If so, why did a respected LS7 tech writer get his new replacement warranty heads measured in 2013 before install and they were out of spec. The guides were in spec but the valve heads were out of concentric alignment per GM spec BRAND NEW. Also a number of replacement warranty engines since that time have had the heads out of spec in less than 10K miles.

See my other post in this thread on how far out my guides were and there were no unusual noises.

BTW the same vendor that does the LS7 heads for GM (Linimar) also under-filled the fluid in about 4000 C7 Z06 e-difs. Guess what failed! QC is not their strong point.

Have your heads redone before your warranty is up or when you do mods that would void the warranty. One fellow on here had the work scheduled two weeks after the warranty expired. Guess what happened during that two weeks, failure and big $$$

Wass

Definitely on some 13 cars, but I'm not sure about the 12 model year. No way to tell if you have one of those engines, but I think the problem would surface before 15K miles of use. I have a 13Z and purchased a GMEPP warranty 30 days before my bumper to bumper expired. No deductible and good until 2020 for about $2K.

https://www.corvetteforum.com/forums...post1592519940
"There have been numerous issues with the 2013 built engines for a rod bearing issue. I've seen a handful of double replacement engines due to the rod bearings fail and all the effected engines has the same date codes on them. They're required to note the original and new serial numbers on the repair order for warranty purposes. I would check to see if those serial numbers are all close to each other. All of the ones I witnessed were all "D" code engines."

guido1205us

Does a new engine actually fix the issue? I would assume a replacement, crate LS7 engine would still be out of spec?

Reason why I ask is that I passed on a 2012 Z07 that had it's engine replaced at around 8k. Dealer said previous owner smelled/saw oil in the exhaust and a certified GM inspector without hesitation authorized a new replacement at the dealership. Although I would have been ok with dealing with the heads myself, they didn't give me the price I wanted in order to pick up the car. That, and I'm unsure of what impact a new engine has on the resale value.

Oh, and OP - need pics.

Unreal

No a new GM issue is not a guarantee of a fix. Still rolling the dice.

Michael_D

Anyone who owns any car with this engine needs to either: 1) get a good warranty and hope it isn't used 2) inspect guide clearance about every 5000 miles for the first 20k miles 3) pull the heads and have them reworked.

Or don't do any of the above, and cry foul on the Internet if you lose an engine.

Sadly, between GM, ignorant dealers, and GM fan boys, truthful disclosure is not widely communicated.

2k Cobra

They changed bearing material around 2012-13. There have been several reports of engines going south on that issue.

With the above years you can worry about bearings and dropping valves..

ICULOOKN