Z51 Rotors Turned?
Thread Starter
Racer
Joined: Aug 2008
Posts: 291
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Z51 Rotors Turned?
I dropped off my '06 Z51 this morning for new brake pads at the dealer. They just told me that my rotors do not need to be turned. There are heavy grooves in a couple of them. I specified I wanted the same pads that came with the car and I'll deal with the dust. Will this be O.K. without turning the rotors? Once and a while I track this car and I need it to brake perfectly.
Tech Contributor
Joined: May 2008
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From: Howell Michigan
St. Jude Donor '09-'10-'11
Race Director
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From: Phila Suburbs 2023 C8 & 2013 650ix
The tech manual says that allowable grooves (scoring) are up to 0.059 inches in depth but if "excessive" scoring is present (I guess that means a large number of grooves even though they are under the limit) they should be resurfaced or replaced.
Personally, I'd have them turned if there is acceptable thickness after turning.
Personally, I'd have them turned if there is acceptable thickness after turning.
Le Mans Master
Joined: Feb 2006
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From: Chandler Arizona
Supporting Vendor
Joined: Oct 2002
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From: Cleveland OH
St. Jude Donor '11,'13
I dropped off my '06 Z51 this morning for new brake pads at the dealer. They just told me that my rotors do not need to be turned. There are heavy grooves in a couple of them. I specified I wanted the same pads that came with the car and I'll deal with the dust. Will this be O.K. without turning the rotors? Once and a while I track this car and I need it to brake perfectly.
Thread Starter
Racer
Joined: Aug 2008
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Likes: 148
Thanks, I've never had drilled rotors before and was unsure if they could be turned or if they needed to be. My only experience with rotors on a Vette was replacing the parking brakes in my '77 and it involved a slide hammer on both rears.
Thread Starter
Racer
Joined: Aug 2008
Posts: 291
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They replaced my pads with part numbers 88909667 and 19169649. Brakes feel fine in traffic, I also had my trans flushed. The last time I had this car on the track my trans temps reached 268 degrees. This is why. http://www.youtube.com/watch?v=ss1mWr-QfGU
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Brett Foote
Team Owner
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From: San Clemente CA
I've done my own brake jobs for over fifty years. That's before disk brakes were standard on auto's. Only one time have I turned the rotors and that was due to them being warped. 
Last edited by VET4LES; Mar 31, 2010 at 06:52 AM.
Race Director
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From: Phila Suburbs 2023 C8 & 2013 650ix
OK, save a few bucks on grooved rotors and the brakes will work just fine. But you may have forgotten how nice new brakes on new or resurfaced rotors feel. The application of brakes is simply smoother and I'll pay for that.
Safety Car
Joined: Jun 1999
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From: Austin, Singapore, Kuala Lumpur, Houston, Dallas, Hong Kong, Elgin, etc.. Texas
I suggest doing a Google search on "sandpaper+rotors".
It seems pretty common and widely acceptable to use sandpaper on the rotors if a) they are not warped and b) no excessive grooves. My 1996 Corvette Helms manual recommended sanding them if they were in good shape.
I recently did the brakes on our daily drivers (non-Corvettes) and my wife's Lexus, I just installed new pads and did not touch the rotors. My car, a Mercedes ML55 AMG, I had a rusty set of OEM Mercedes rotors that I removed 2 years ago during the last brake job that I took to the local brake shop and had them turned only to clean them up and get the rust off.
I sanded then with 100 grit paper to remove the machine marks, washed them with Simple Green, and then wiped them down with denatured alcohol.
I looked at the Corvette rotors the other day and they look great. If they look that way when the pads are worn out, I'll just sand them down and install new pads. 100 seems to be about the right grit. Use an orbital sander if you have one.
One thing you have to worry about when getting new rotors or getting old ones turned is excessive run-out. So don't be afraid to just sand them down and put new pads if they are in good shape.
It seems pretty common and widely acceptable to use sandpaper on the rotors if a) they are not warped and b) no excessive grooves. My 1996 Corvette Helms manual recommended sanding them if they were in good shape.
I recently did the brakes on our daily drivers (non-Corvettes) and my wife's Lexus, I just installed new pads and did not touch the rotors. My car, a Mercedes ML55 AMG, I had a rusty set of OEM Mercedes rotors that I removed 2 years ago during the last brake job that I took to the local brake shop and had them turned only to clean them up and get the rust off.
I sanded then with 100 grit paper to remove the machine marks, washed them with Simple Green, and then wiped them down with denatured alcohol.
I looked at the Corvette rotors the other day and they look great. If they look that way when the pads are worn out, I'll just sand them down and install new pads. 100 seems to be about the right grit. Use an orbital sander if you have one.
One thing you have to worry about when getting new rotors or getting old ones turned is excessive run-out. So don't be afraid to just sand them down and put new pads if they are in good shape.
Last edited by Mez; Apr 1, 2010 at 07:13 PM.
Tech Contributor
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From: Howell Michigan
St. Jude Donor '09-'10-'11
As far as braking quality, there is no difference if the new pads are bedded in properly after installation compared the turning the rotors just for the sake of replacing the pads.
Instructor
Joined: Mar 2010
Posts: 112
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From: NJ
It's what us machinists call an "interrupted cut" on the lathe, but I've done cuts like that on parts before (never brakes though). It's just a little harder on the cutting tool bit because it introduces impacts to each revolution.
read this: http://www.stoptech.com/tech_info/wp...rakedisk.shtml
read this: http://www.stoptech.com/tech_info/wp...rakedisk.shtml
Last edited by WCLW; Mar 31, 2010 at 06:33 PM.
Safety Car
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From: Austin, Singapore, Kuala Lumpur, Houston, Dallas, Hong Kong, Elgin, etc.. Texas
If the brakes do not squeal, the pedal does not pulse, and it stops as it should then you should be fine.
Burning Brakes
Joined: Feb 2008
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On all my cars, I only have them cut if the brakes had worn through & grooved them or they got warped. Other then that, I use sandpaper on them. Why shorten there life span if you don't have to.
I do agree though that they feel pretty nice after a good cuttin'
I do agree though that they feel pretty nice after a good cuttin'
Last edited by vettemann62; Apr 1, 2010 at 07:53 PM.
Tech Contributor
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From: Charlotte, NC (formerly Endicott, NY)
I just throw a set of pads on if the rotors aren't excessively grooved. Have been doing that for close to 40 years without turning rotors. It is even hard to find someplace that will turn rotors nowadays. Used to be that every auto parts store had the ability to turn drums and rotors. I don't know of a single store in my area that has the ability to do that now.
Bill
Bill