chevynovaguy72

Hopefully this isnt a repost - if so feel free to remove it.

#13-06-01-001: Information on Customer Questions About Valve Guide Wear - (Jan 14, 2013)

Subject:

Information on Customer Questions About Valve Guide Wear

Models: 2006-2013 Chevrolet Corvette 427, Corvette Z06

Equipped with 7.0L V8 Engine (RPO LS7)

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Customer Concern

Some owners of Corvettes equipped with the LS7 7.0L V8 engine may ask your dealership to check their vehicle for valve guide wear because of information that has been distributed on the internet, primarily at Corvette enthusiast sites. Due to these postings, some customers that have not had an issue may ask to have their vehicle checked. If a customer presents their vehicle and requests the valve guides be checked, the following information may be helpful to you and alleviate any concern for your customer.

Valve Guide Wear / Noise Concerns

To address any concern the customer may have, listen to the customer’s request and ask the following questions to differentiate if the customer has experienced a correctable engine concern or has anxiety over information they may have read.
Important: It is important to investigate all concerns and relay good factual information to your customer. If a customer indicates a concern about valve guide wear, it is possible they may have a valid unrelated engine issue, and do not know how to express the actual concern.

1. Have you experienced any concerns or difficulties that would indicate an engine problem?
2. Is the Check Engine Light ON? Does the vehicle exhibit any starting/running concerns?
3. If the concern is noise related, ask for a description of the type of noise heard?

Once the information is collected, and the nature of the customers concerns are known, here are some guidelines for appropriate actions:

•For any driveability, starting, running or found DTC code issues, if the car is under the respective warranty period, repair the vehicle following normal diagnostics as outlined in the Electronic Service Information (SI). If the vehicle is out of the warranty period, explain the available options for the customer.

•If the customer indicated a concern with engine noise, warm the vehicle to operating temperature and compare it to similar vehicles. If the vehicle does not exhibit unusual noises or malfunctions, the customer should be told there is nothing to indicate the need to disassemble the engine to determine valve guide wear. The LS7 is a high performance motor and as such is built with an emphasis on power while retaining the lowest possible noise and vibration characteristics. Some valve train noise may be evident, which is a by product of the performance nature of this engine. General Motors has reviewed paid warranty claims for valve and head replacement for the Corvette LS7 and the numbers of incidents are very low with no indication of an excessive wear issue.

•If the customer’s sole concern is based on information collected over the internet, with no verifiable symptom, and the customer insists the engine be disassembled and verified, it should be explained to the customer that any charges for the inspection would be at the customers expense. Valve guides are an internal engine component subject to wear over the life of the vehicle. If there is excessive wear (beyond the indicated service limit) after the investigation is completed, GM will cover the inspection and repair expense for vehicles covered under the Powertrain Limited warranty.

Aftermarket Equipment and Valve Guide Wear

The use of performance engine modifications has been found to accelerate valve guide wear. Replacement aftermarket mechanical parts, or software calibrations, may adversely affect the wear of these and other components. Any modification to the engine of GM vehicles voids the powertrain coverage portion of the vehicle warranty. For additional information on GM policies regarding aftermarket equipment and calibrations, please refer to the GM Service Policy & Procedures Manual, article 1.4.14 (Voided Warranties and Branded Titles) and article 1.2.2.12 (Non-GM Parts & Equipment and Original Equipment Alterations), along with the latest versions of Corporate Bulletin numbers 09-00-89-016 and 09-06-04-026 for additional information.

Hirohawa

Thanks for posting!

VETTEMANN

I had not seen this. There you have it, an official response from GM at least acknowledging the concerns of this forum:

"If the customer’s sole concern is based on information collected over the internet, with no verifiable symptom, and the customer insists the engine be disassembled and verified, it should be explained to the customer that any charges for the inspection would be at the customers expense. Valve guides are an internal engine component subject to wear over the life of the vehicle. If there is excessive wear (beyond the indicated service limit) after the investigation is completed, GM will cover the inspection and repair expense for vehicles covered under the Powertrain Limited warranty."

I wish someone from GM would follow-up and now post on here what is the most likely, informed, cause of any excessive wear, if it is found.

VETTEMANN

I'm thinking, as if we were owners of Ferraris, we might all plan to take our 427s to dealers at 10,000 miles and have an inspection done to see whether or not we are 'lottery winners.'

I wish I knew who the most technically competent (engine wise) Chevy dealer is near Austin, TX. Might be good to know that recommendation for every LS7 owner in every major metro?

probabilist

GM has responded in a reasonable way and says the event is very rare. Some drama queen internet people have overblown the issue---kind of like the oil burning of a small number of LS1 engines awhile back.

Everyone can now stop yapping about it.......

Turbosixx

See that, there's nothing wrong.

ZR1Cat

I am glad to hear those trouble making internet "Corvette enthusiaist sites" have yet to start any rumors about the LS9 engine.

MudZ06

Very interesting. Take care of your heads people! Especially if you are outside warranty.

wolf8218

I think this post made my year.

/tears

BearZ06

What a relief to read that statement.

b4i4getit

Just wait until the LT1 comes out.

240sx2jz

Pppphheeewwww, what a relief. For a second i thought there was a problem with my car that had guides worn 7X the sevice limit at 20k miles. Good to know i was just being a whiny little bi@tch corvette enthusiast, internet jockey....

mistermog

What a douchebaggery thing to say.... My car is at Chevy RIGHT NOW as we speak because of the social media rep suggesting i take it in. I know for a fact my guides are worn, I've done the dial gauge "wiggle test". So if they tell me nothing is wrong, I'm done with Chevy and GM and buying a mustang.

BearZ06

GM has probably replaced more engines than heads/valves. It's all in our "heads" anyway: "has anxiety over information they may have read".

wolf8218

Let us know what happens

mistermog

They actually just called back, they said it would take 3 hours and about 275 more bucks to dig into it to measure the guides. I'm having a hard time swallowing 350 bucks to measure guides when I'm obviously well out of warranty.

Sigh

wolf8218

In that case why don't you do it yourself?

cruzin2

GM is running a business, not a charity. I think this response is very reasonable and also shows the problem is rare but also that people are concerned and GM is working with their dealer partners to help their customers. Also they are stating that they will cover valid claims. I see no problem with this response. I have an 09 Z btw.

mistermog

Well, I understand the response and not faulting the dealer at all. I just dont like that I have to pay because of something wrong with the manufacturing of the product. Just because it didnt fail soon doesnt mean it isnt their fault.

wolf8218

Technically your product is still working as intended because it lasted through your warranty period.

Unless you can demonstrate that there is a defective part which they are still responsible for (which they are not) then it really isn't GM's fault.