427 engine (part 2) - RHS block

[Rich Z]

Oh, there have been LOTS a straws that almost did that.

But surprisingly, Connie was the one who told me to just buck up and keep on plugging away at it. I was really worried about this all ruining our first couple years of retirement for us, which it did, but she just did not want me to give up on it.

I will say this, Connie says I no longer grind my teeth in my sleep like I did when all this nonsense was going on.

[shakedown067]

That's a VERY good wife you've got there. She might be a keeper. LOL I'm pretty sure my wife would love for me to sell the Vette, but I don't blame her. It can take a lot of my spare time, that I'd rather spend with my young kids (3 and 1).

[Rich Z]

OK, had quite a few startups since replacing the TAC module and haven't had a single incidence of that REDUCED ENGINE POWER error showing up. So I guess my shot in the dark hit the target after all.

[85vette]

Good to hear. Nothing worse than an intermittent electrical gremlin.

[Rich Z]

Originally Posted by 85vette

Good to hear. Nothing worse than an intermittent electrical gremlin.

Actually, yes, there is. This thread is an excellent example, I think.

[85vette]

Originally Posted by Rich Z

Actually, yes, there is. This thread is an excellent example, I think.

I mean AFTER all that.

[Rich Z]

The car has actually been running pretty strong, and no real notable problems except for an intermittent drive train noise. Back in September it seemed to get MUCH worse, and I benched the car for a while and started considering that I was going to have to pull out the drivetrain to fix or replace something. But I didn't want to jump in blindly not knowing what, exactly, I was looking for. So I started doing some research, looking for YouTube videos of people experiencing the same type of noise. I had my own video taken back in October of 2012 that clearly showed the problem in audio.

And I also sent off emails to a couple of people asking for their opinion of what they were hearing from the above mentioned video. The email I sent them was roughly the same as below:

I'm hoping you can help me identify a problem with my 2002 Corvette Z06. I bought a transmission and differential from you via South Georgia Corvettes in Thomasville, GA, back in 2012. The car was a mess when I got it back, and it took me over a year to get it mostly straightened out. During that time I had to replace the torque tube with driveshaft because the carbon fiber driveshaft that Pfadt sent for my car was incorrect and too long for my vehicle. The installer did not catch the mistake, nor did South Georgia Corvette when they worked on it. So the torque tube got destroyed, as well as the clutch, slave cylinder and flywheel. The pilot bearing had been bored into, but there didn't look like there was any damage to the crank itself.

Anyway, I've had an intermittent drive train noise ever since, and possibly even before all the above was replaced, but I just can't recall with all the other noises the above damaged caused. The noise seems to happen most often going from a dead stop and when I am taking pressure off of the clutch pedal so that the clutch pressure plate engages the disk. It will sometimes, although more rarely and less noticeably, happen when changing gears while accelerating. Again, this is when I let off of the clutch pedal and the drivetrain picks up the load from the clutch engaging the disk. Happens in reverse as well as forward gears. I can often feel a strong vibration associated with the noise directly on the shifter handle.

I've spent a lot of time looking at videos on YouTube and asking around, but so far just cannot pin down the most likely cause of this noise problem. I've been trying to wait it out to see if it will just work it's way out, or be consistent enough that I can make it happen on demand 100 percent of the time, but so far that's just not happening.
But obviously it puts me in a bind, as I just do not trust the car to not fail me on a long trip with it and it's wearing on me.

I am prepared to pull out the drivetrain myself and fix or replace whatever needs to be done, but I would REALLY like to have an excellent idea of exactly what I am looking for. So I'm hoping you can give me some guidance. I am putting a link here to a YouTube video I took back in 2012 to show you (and let you hear) the noise I am talking about:

https://www.youtube.com/watch?v=_fKbJ23MTdE

Again, this happens when I am taking pressure off of the clutch pedal and the clutch is easing into moving the car forward. At all other times there is absolutely no noise from the drivetrain that I can determine. I figure you guys have probably seen more than your share of drivetrain problems, and hopefully heard this exact same thing and KNOW what the problem is.

So would you mind helping me with this? This has been dragging on for a long time now and I would really like to feel that my car is finally finished and the problems GONE.

Thank you for any help you can give me with this. If there is anything I can check for you, I have the car up on my lift right now and can take videos with audio, or anything else you would need.

I'm not sure the people involved really want their names named, so I'll just put quotes from their email replies here without names attached.

From SHOP #1

That sounds like normal clutch noise from a ceramic or sintered iron disk. What type of clutch is in the car.

From ME

It's a Centerforce clutch. The corvette specialist at the local Chevy dealership installed it when my drivetrain destructed, and he did not want to go with anything radical. It seems to be holding up well enough. So it's definitely not any sort of racing clutch of any sort.
I broke in the clutch carefully, and do not race the car, so it's not like it's ever been abused. Honestly, it's pretty loud when it happens, so I would be reluctant to think the noise is "normal".

Any ideas?

Thanks,

From SHOP #1

Sounds like normal clutch noise to me and our other sales guy who was sitting at his computer and said whats that a clutch with out even seeing what I was watching

From ME

Well heck, you guys are the experts in this stuff. Being "normal" it's nothing I really should lay awake at night worrying about? Just get a different brand of clutch next time around?

Thanks for your help with this.

From SHOP #1

Correct we would never recommend a Centerforce clutch for any application as we have not had great luck with them. But you are not having any problems with it so looks to be working for you.

======================================

From SHOP #2

It is not uncommon for a performance clutch to be noisy and chatter as it slips. A spec5 for instance has a squeal that will make a guy cringe. This could be an issue that never goes away until you use an organic clutch

From ME

It's a Centerforce clutch in there that the Chevy dealership vette tech recommended. Actually he refused to go with the dual disk I wanted. So I don't think this is an especially "high" performance clutch. Heck, for a while there I was thinking it was just sand getting in the clutch while driving down the sand road we have through our property. It is pretty loud, though, so it's been kind of nerve racking to me. So you think it's nothing for me to worry about and just try a different brand next time around?

Thanks for your help with this.

From SHOP #2

Centerforce may be the worst choice for any car ever made. So many noise complaints on that brand. Katech has a package available to install the ZR1 dual clutch in a c5. Best ever for stock feeling and NVH as well as able to hold a great deal of power. After that, my choice is either a quartermaster or RPS clutch. RPS being the more aggressive clutch.

Now I want to say here that this is nothing against the guy at the local Chevy dealership at all. I believe the guy is exceptional in what he does, but just do not believe that he is (or was) on top of the aftermarket options available. He chose what he thought was best for my situation, which was what he wanted to install to get my car on the road without going to anything exotic and possible questionable as to the suitability to my street driven vehicle. I would still go to him in a heartbeat if I needed work done from the dealership.

Anyway, this is where I am at right now. Interestingly enough, when I moved the C5Z from the garage bay it was in to the bay with the lift, the drivetrain didn't make even a peep. So I think I need to continue along driving it "as is" and just put up with the intermittent drivetrain noise. It will either get better, get worse, or stay the same. But in the meantime, I think I'll start researching a new clutch and try to decide on one for that time when the clutch NEEDS to be replaced. Once I have a brand and model targeted, just keep my eyes peeled for someone running a sale on it and then put it up on a shelf waiting for the time it is needed.

Yeah, it is embarrassing to have the car make that squealing noise now and again. But I don't believe the embarrassment is quite enough, at least yet, to convince me to pull out the drivetrain in order to get rid of it.

[Rich Z]

While I was thinking I was going to be pulling out the drivetrain, I went and took a bunch of photos so I could reference them when I may need to. Guess I might as well store them here.

[Rich Z]

And the last batch of photos.....

[mrr23]

well that's really wrapped up and pretty. if it's clutch noise, i wouldn't worry about it for now.