rockinSeat

Hey Fellas, 07 Z06 with 33k miles here. I got my heads replaced under warranty in 2013 at 20k miles. I have GMPP warranty left until February, so I'm wondering what to do. The car has always made a ticking sound around 2k RPM both before and after the headswap. I don't know if that is a problem or not. I would love to have the GMPP pay for the reworked heads and install, but I don't know if the guides are worn or not; I'd rather have AHP, but I live in Colorado Springs. Finally, I'd consider doing the swap myself, but it would be the biggest car repair I've ever done. I read through the diy instructions here on the forum, and it didn't look too hard, but I could use some more instructions and pictures. Could someone please send me the pages I need from the service manual or something? Has anyone used the alldatadiy.com? What is the hardest part about it?


​​​​​​Anyone know of a shop in Colorado that takes GMPP?

Merry Christmas. I would have moved on this earlier, but with a new job, new home, and newborn, it has been a busy year.

outhouse

The heads are easy to do at home, I did mine outside and even tackled the cam while I was in there.



Probably normal, but when heads are off you definitely want to inspect cam and lifters.


Mine made a lot of noise over 2k and everything was in like new shape.


Now after cam and heads it ticks under 2k as well as the typical sewing machine sound from an aggressive valve train.


AHP will do you good no matter what, just mail your heads off to them.

wjnjr

Sounds familiar, I just went through this last month. Here's my $0.02

First thing to do is have a wiggle test done and find out where you stand. Pick a shop that is familiar with the LS7 valve guide issue and takes GMPP. You might choose a Chevrolet dealer or you might choose an independent shop, depending on who you're comfortable with. Ask around for recommendations and check them out in person.

There's a (good) chance your replacement heads will show excessive valve guide wear at 13k mi. If they do, it's been my recent experience that GMPP will pay for the AHP basic pkg 4 rebuilt heads (less the core charge) and the labor and materials to R&R the heads.

If they don't show excessive guide wear, then you can make a decision on what, if anything, to do next.

Hope this helps. Good luck and keep us posted.

rockinSeat

Thanks for the replies fellas, anyone that could send me the shop manual pages or anyone with alldatadiy that knows whether it is worth it?

outhouse

There are two picture full DIY videos her for LS7 headswap with all torque specs.


I also used the C6 cam swap DIY because it was identical and gave a few different views and all specs needed

rockinSeat

Those would be helpful, I seem to only be able to find one and I didn't see much on YouTube other than failed wiggle tests. If you have those links handy or if you know how to find them, could you please post?

https://www.corvetteforum.com/forums...-headswap.html


Sorry for being dense.

outhouse

That link is the one I used and this one below.


heads are easy without cam, one day they are off with minimal skill


https://www.corvetteforum.com/forums...s-of-pics.html

rockinSeat

So I took my car into my local Chevy dealer and they listened to me and all of my concerns about the valve guides. I asked them what we could do- they explained that customers come first and they would get to the bottom of it. They took the car for a short test drive and agreed the car was making excessive ticking noise. They started with a finger wiggle test, but none of the valves moved, so they did a full wiggle test with measurements ...Drum roll....Guess what the answer was for my new in 2013 warranty replacement heads with 13k miles was? All in spec under .0037. I even get the results written up in a report.

As for the ticking noise, they believe it to be the rockers and lifters, so they are replacing all of those under warranty. They will also be changing the oil as a part of the process. And if the noise doesn't go away, they will keep at it.

i have asked them to check for irregular wear on the rockers as my friend told me that could mean cam wear. Anything else I should ask or any advice you guys have?

I felt like sharing this good experience with the dealership since most of the time people share the bad ones. As far as I know, the dealer went above and beyond to help me with a wiggle test. I think the secret is a good tip after picking up the car when it's done... Maybe we should all do that.

golfinz

Sounds like you have a great dealer and service center! Might consider extending that warranty if they are that eager to work on the car.

outhouse

It is actually normal and I highly doubt your 13k lifters or rockers even have a bit of wear. But they do get paid to replace parts needed or not. It is an aggressive valve train and they all tick to some degree.


Pulled my stock cam and lifters out at 43k that made a terrible ticking noise over 2k rpm. Every last lobe and lifter was in new condition and rockers/trunions in perfect shape and they were reused.



Awesome

rockinSeat

My new factory replacement heads have 13k on them, but the rockers, lifters, and the rest of the car have 33k. Think they could be the source of the noise? In my opinion, I have the 2k RPM tick, but dealer hears tick from 1-4k RPM.

rockinSeat

So what was making the noise?

wjnjr

Good news about your valve guides, and it certainly is refreshing to hear of a good service experience. Please post the wiggle test numbers when you can.

outhouse

Just design alone. Parts were all like new. Ticking is normal in many of these cars.

rockinSeat

I could agree if all of these cars ticked, but why some that don't? I always thought once the oil heated up the tick stopped, but now I can't remember.

outhouse

Most do tick.


Oil temp plays no role

rockinSeat

Well I heard back and the new rockers and lifters are installed. My service advisor says there's a marked decrease in the ticking sound but there is still a tick that they think is a fuel injector. They are going to compare the sound to other Z06s as they suspect it might be normal. I'm anxious to get the car back and give it a listen. I also get the wiggle test results back. They said most measured .0012. thoughts?

outhouse

You should be good to go.


I had my mind set to have AHP do their #4 regardless so I don't have to worry about them for the next 7 years. I don't drive much yearly. I had 4 out of spec.


You should probably check again in 10-20k miles just to stay on top of wear so you can get the heads done when their close to their wear limits.


If you ever decide to do mods, get them done at that time.

rockinSeat

Well I couldn't believe the difference in sound after I picked the car up. The new lifters got rid of a ton of the ticking sound. SA said several were bad but it makes sense to replace all at once. Says the remaining sound is due to the injectors. I said how do you know? Chassis ears. Two injectors on the driver's side bank were distinctly louder than the others. SA also compared to another Z06 and found it had noisy injectors on the right bank. We went for a test drive and for the most part the car is quiet as a Buick. SA asks hear that sound that sounds like a baseball card in the spokes? That's the noisy injectors.

So is he right? He says all valves guides were around .0012. I felt the baseball card in the spokes was a great analogy considering how hard it is to describe what we hear. Maybe I haven't spent enough time behind a sewing machine to know what that sounds like.

So, I got all that diagnosis, wiggle test, lifters, oil, and a wash for a deductible. I couldn't be happier with my SA and the dealer.

Anyone think the baseball card analogy could be its own thread?

rockinSeat

I forgot to mention they also peaked at my cam with a borescope and they could not see any wear.