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Corvette Today’s News That “Corvette Fever” Returns

Corvette Fever magazine has not been published for a while. But Alan Colvin, a walking encyclopedia of GM cars as well as Corvette, has purchased the rights to Corvette Fever and has revived this publication! https://anchor.fm/steve-garrett/epis...-Colvin-euvkq2. Your CORVETTE TODAY host, Steve Garrett, visits with Alan to talk about the books he's written on Corvette and other GM products, his history with the old Corvette Fever magazine and how he plans to revive the publication. Plus, listen to this podcast and register to win one of 3-two year subscriptions to Corvette Fever that we're giving away exclusively on this episode! Listen to this CORVETTE TODAY podcast and win a subscription to Corvette Fever magazine!!!
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SGTMAJ USMC AUTO & TOY HAULER Joins MECF As A Featured Forum Vendor.

Welcome to SGTMAJ USMC USMC AUTO & TOY HAULER! We are so happy to have you now join us as a MECF Featured Forum Vendor. We can not wait to help your new business grow. We know you will provide a great transport service to our members and others!
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Z06 Potential Patents

As we get ready for the Z06’s debut sometime in the next year, IMO time to brush up on the 23 GM C8 patents — many of which are Z06 potentials: https://www.midenginecorvetteforum.c...alized-patents
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Whine from back end (plus poll)

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  • #16
    Originally posted by Murray20c8 View Post

    And politely let them know you will. "You now have left me no recourse....."
    Yeah, I hear you. To me this is really dumb, all kinds of potential liabilities for them if a rear end seizes up. Not exactly sure why the service manager is treating this so blithely, if it's covered under warranty it's not like it's on his dime.

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    • #17
      Originally posted by Red C-8 of Jax View Post
      Is it possible for you to try another dealer for another opinion?
      Good question, anyone ever run into anything like this and have better luck switching dealers?

      Comment


      • #18
        Originally posted by improviz View Post

        Hi, I did post two links in my post to PDR vids I took last week. Are they not working? Thanks
        They work, I could hear the noise you're talking about. Find a different dealer, I don't think that sound is something to be ignored in a brand new car.

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        • #19
          Originally posted by improviz View Post

          Good question, anyone ever run into anything like this and have better luck switching dealers?
          As the car's service history is now in the same database, the new dealer will see what the previous dealer and GM said. So it may be harder to get an unbiased view unless the new dealer is much more understanding. Hope they simply don't read GM's assessment from the original dealer and figure there's no money in it for them if they were to pursue it.

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          • #20
            Well, he didn't actually try to submit a warranty claim and have it denied, I think in all honesty he's trying to avoid it which is weird. Not sure if it's just that he doesn't want to work on it, or what.

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            • #21
              Warranty approvals beyond a minimal amount must as of a few years ago, now be reviewed and approved by the Regional Warranty Approval Supervisor. Conversely if a dealer does not want to approve something, the RWAS can override the dealership and authorize it (meaning GM will pay the dealer in full for that warranty repair and direct therm to do it).

              GBA Black; HTO Twilight/Tension interior; Z51 & Mag Ride; E60 lift; 5VM visible carbon fiber package; 5ZZ high wing; FA5 interior vis CF; ZZ3 engine appearance; 3LT; Q8T Spectra Gray Tridents; J6N Edge Red Calipers; SNG Edge Red Hashmarks; VQK Splash Guards; RCC Edge Red engine cover; VJR illuminated sill plates. Lifetime, annual contributors, and 23 year members of National Corvette Museum. Home is the beautiful Pacific Northwest.

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              • #22
                From your first video, that is really loud.
                So what is common when in different gears and at constant speed is the countershaft and it's bearings (not likely a cause but possible), transfer gearset (again not likely a cause but possible), the transfer gear shaft/pinion gear shaft bearings, the park pawl system, since it is a Z51 there is also the Ravigneaux planetary gearset part of the ELSD that is used for differential action (again not likely a cause due to no differential action in a straight line, but possible), the ring and pinion gearset, diff carrier side bearings/axle bearings, CV axles, wheel bearings and brake rotors.
                They could put on the "Big Ears" (basically an electronic stethoscope with multiple pickups and channels) or use a NVH diagnostic tool to isolate the area the noise is emanating from to focus in on the problem area, but they might not have these tools.
                They might also have trouble getting GM's approval to spend this diagnostic time -- very few dealers will actually eat this time in favor of customer satisfaction, but there might be some.
                Can you try to duplicate this condition in the 40 to 50 mph range while going through as sharp a corner as is comfortable to see if the noise changes?
                That could isolate or help to rule out anything that would be turning different speeds while cornering -- it might speed up while turning one direction and slow down while turning the other direction and help to isolate it to an axle bearing, CV axle, diff bearing, etc.
                As for the differential oil/diff fluid, the diff is integral to the DCT so it shares the DCT's lube oil and hydraulics so the DCT fluid/oil level ensures the diff has the correct amount of oil -- hopefully they at least checked the DCT oil level.
                TPW March 2. 3LT, Z51, FE4, Black GBA, ZZ3, Black interior with Red seats/red stitch HU0 & 2 tone TU7, E60, J6N, RIK, Q8Q, etc.
                Medicine Hat, Alberta, Canada

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                • #23
                  Neil, thanks so very much, this was most informative and helpful. I know a nice road full of S-curves nearby which is perfect for this, but during the week it's got a fair amount of traffic. Will give it a go over the weekend. Thanks again!

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                  • #24
                    Not easy to do but someone could put the vehicle on a dynamometer and use recorders to analyze the sound hot and cold. I say it is axle noise and the sound varies due to the expansion of different materials, primarily aluminum. The backlash is set at cold temperature and expands as things warm up. The range of noise can be varied somewhat by adjusting the settings but will always be there at some speed and temperature.

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                    • #25
                      Corv63 I agree, the noise definitely has a temperature coefficient. It is less severe until the vehicle has been driven for a bit, and conversely was noticeably louder before it started cooling off outside. So it's at its worst when vehicle has been driven for a bit and it's warm outside.

                      Also I noticed that when I was taking vids for the other issue it has, the DCT issue (diffferent thread), after I did a few runs to capture that issue on PDR (which involves flooring accelerator for a few moments), it was more noticeable then would quiet down after I drove for a bit and things cooled down. To me it just seems like the diff wasn't properly set from the factory and over time as miles accrued and things loosened up, this problem showed up.

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                      • #26
                        Mine has ZERO to do with temperature - Cold is identical to warm and I discovered today it's there no matter how fast I go - Today maxed at 85 and it was there...

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                        • #27
                          Neil H I did try going around the S-curves at steady state speed, observed no change in pitch or volume.

                          Also, I took another video over the weekend. In this one I don't vary speed so much, try to keep it at steady speeds for longer. Have a listen:
                          https://vimeo.com/499402442

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                          • #28
                            I have this same issue with my 1LT (no Z51). I get a whine in gears 6 & 7 when I ease off the accelerator or slightly press the accelerator. I noticed this when I got the C8 and now have over 900 miles. I will bring it up with the dealer tech.

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                            • #29
                              I'm making a service appointment too... Will report back - I suspect some guys drive on rougher roads/more music/hearing loss/sport mode and thus can't hear what we're talking about.
                              Last edited by GaryCoral; 01-12-2021, 02:22 PM.

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                              • #30
                                Well... Dealer told me it all sounding normal back there - Only thing left to do is get a ride in another C8 to figure out what "Normal" is.

                                Comment

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