Mar48

Hey all just wanted to write about my recent experience:

I've been planning to get my heads inspected for some time and took my car to a local Chevy dealership (Dealer A). I was quoted $3K just for the inspection and they said they had never heard of a valve issue.... Anyway, I decided I wasn't going to spend $3K to inspect, so I got a quote from dealer B and they said the same thing... No point in doing the test yada yada it's going to take a lot of time.

I had Dealer A do a quick inspection and they heard a squeaking noise coming from the rear of the engine on the driver side. I could hear a decent amount of valve train noise but did not hear what I considered squeaking. Dealer A at this point said that they had never heard this noise before (Corvette Tech had some others listen and they concurred). So, they said I would need to take a part the engine to diagnose. They said they rarely if ever had to take a LS7 apart... They thought it might be that the camshaft was damaged (scored), the lifters had metal deterioration, both, or a bearing failure. The car drove absolutely perfect with just some noise (and a little burning of oil - .5-1 quart/3000 miles) so I was shocked.

I decided to get a 2nd opinion and Dealer B inspected the car, could not hear the noise, but said my belt was cracked and that was the only problem with the car. They thought that might be the squeaking noise that was heard by Dealer A.

Brought the car back to Dealer A and told them what Dealer B stated. Dealer A took the belt off and still heard the noise. They kept their original recommendation and it was agreed that we would split 50/50 the cost of the diagnosis/repair. They did a goodwill warranty - my car is 4-5 months out of warranty and I've only driven it 500 miles this year. Not to mention I had the car inspected by dealer A last year and they did not find anything (the noise my engine makes has not changed since then in my opinion).

They took apart the engine this week and low and behold... Cylinder 5 has a valve that wiggled at .03. They are convinced that is the cause of the squeaking. They have not found any other damage inside the engine.

Sorry for the long winded story - my question is do you think the valve could've caused the squeaking noise they heard?

Also, this just proves GET YOUR VALVES CHECKED!

Mine is an 09 w/43K miles and never had one issue... the car drives PERFECT.

Luckily, I am getting 50% of whatever the bill is paid for by Chevy. I feel fortunate to have caught the issue before I had a valve drop. Will update the thread with what the dealership decides to do (they mentioned replace heads possibly)

Dirty Howie

Good story and good luck. Looking forward to the rest of the story .....


DH

LawrenceFromTorrance

Let's see: GM knows there is a problem and that a (high) percentage of Z06's will self destruct. You've got about 43K on your car and according to GM it really shouldn't last longer than that so you should pay. I'm sorry getting 50% off is not right GM knows there is a problem, GM built your car wrong this is 0% your fault and 100% GM's fault so why are you sharing the cost of their FU? I know you feel lucky because they could have tried to stick you with all of the costs but GM is still screwing you. Anyhow good luck with the repair, it really doesn't sound like the dealers in your area are very knowledgeable. I would push to replace the heads completely and the rockers also.

RamAir972003

The dealer is full of bs yea squeaking caused an 90k car to have valves out of spec do they honestly expect you to bealive that. I would tell them either they fix the ongoing problem
that gm knows about, present them with proof that this a problem and talk to someone that will listen..i wouldn't split anything with them tow the car somewhere that will work on it and just get new heads...period

JUSTAC6

I agree with if your gonna pay have another shop work the heads but if the car is out of warranty and they don't have to pay half of anything then that's a good deal IMO. I am sure the new part will be warrantied but if they only plan on fixing that 1 head well once again it isn't worth because oem is too damn much and I would rather pay for an upgrade.

ctsv510

If it was 0.03 that is waaaaay out of spec! About 4x if you use the (wiggle/2 - 0.0005) formula.

I believe it would be the first time anyone has described a worn valve guide causing a squeaking noise.

Homeboy77

$3k just to do inspection? Wow. I would just put the $3k to new heads and be done with it. However, in your case, you should fight them more on this repair. Good luck.

nitrojunky

not sure i'd want to even pay 1/2 cost to put in a new set of stockers.

RedZ4me

Find a new dealer....fast! don't pay anything, get the heads done right somewhere else

LFZ

Where are you located so that those that are local know where to stay away.

'06 Quicksilver Z06

carpe dm

Good luck.

Bill Dearborn

It all depends on how they do the inspection. The service bulletin uses a sheet out of the FSM that shows the inspection is done with the heads removed. It sounds like the mechanics came up with an excuse to reduce the cost (the squeaking that only they could hear) and to get the engine torn down. Since an issue has been found he should start talking to the Service Writer about contacting GM to see if they will cover the complete repair.

There are plenty of dealers that have never had an issue with an LS7 engine and the bulletin is buried in thousands of other bulletins so it is easy to believe two dealers in the same town have never heard of the problem. Hell, my dealer replaced two engines that experienced valve drops (mine and another guy's) three years ago and still hasn't heard of the so called LS7 valve guide issue. The last thing he wants to do is go in there and screw himself by causing a furor over something that isn't clear cut and clearly isn't the dealer's fault. His car is a few months out of the Drive Train warranty and this is the time to ask GM to help him. Let them be magnanimous Vs being confrontational with them.

There are some people who have trouble with dealerships on a regular basis and there are some people who can go to the same dealer and get excellent service and respect.

Bill

Dirty Howie

Good advise there


DH

Vettes R Us

erikszr1

if it was squeaking and or chirping then maybe you had a lifter going bad. this is quiet common on LS engines so it doesn't surprise me. I would ask to see camshaft and the bad lifter. it will be plain as day if it is bad. bad guides do not make any real noticeable noise, hardly any to an untrained ear. this whole thing makes be think they felt that if your that concerned about your car and would pay to have piece of mind and they were willing to take your money to do so. this job pays fairly well and a good tech wont mind doing it. ask to see bad parts.

clogan

Dude!
Your 50% of a dealer repair will likely be far more than 100% share if done at an LS7 specialty shop. And the Chevy dealer will repair with the same old crap heads and valves that were bad to begin with. You need to report these clowns here on the forum, and with the BBB, then get yourself and your car out of there as soon as you can!

Vito.A

I am happy you found the issue before a catastrophic failure. I'm also pleased GM is going to cover 50% of the cost. However, if this were my car I'm not sure I would want them to repair it back to original specs. It made it to 42k miles this time with all new GM parts. Usually you get about half the life from a rebuild. If you plan on selling the car, then you should be fine. If you plan on keeping it, then you have just kicked the can down the road for real repairs which involve replacement bronze guides and replacing the hollow stem exhaust valves.


By the way, I doubt a guide worn .003", or even .030" would cause squeaking. However, it does give you the reason to pull the engine apart and find the real reason.
Best of luck!

Mar48

Thanks for the helpful/thoughtful post.... The car is already apart so there's no turning back. I made my decision knowing full well I had other options, but I deemed this to be the best one for my situation and feeling related to heads.

Bill - How would you go about contacting the service writer? I've been speaking to the Service Advisor the whole time and he basically said that 50% is the best they'll do.

I do completely agree that the head should be fully covered since it is a known issue and .03 is VERY out of spec... no way it was within spec last year considering I only put about 500 miles on it this year.

I'm going to try to get it fully covered, but not sure what the best route to take is? Has anyone had much luck with Chevy Customer Service? I spoke to them a few times, might try again.

Couple more notes:
- they checked the lifters and found nothing
- since the repair will be considered a goodwill warranty they will not let me have the spare/old parts and they also will not replace with anything but OEM
- Also I went into this thinking I had a different issue based on the sound they heard (lifters or cams) so I did not want to just put new heads on it and be done with it.... If I had to replace Cams/Lifters/Valves it would be a lot of money anywhere... I doubt it would've been cheaper than what I'll pay.

erikszr1

bad guides do not squeak, ever. so that's not the noise you had. I wish they found a bad lifter. then you would get a new lifters, cam and heads. that would be good. oh well.