Rear Brake rotors
Thread Starter
Advanced
Joined: Oct 2015
Posts: 99
Likes: 1
From: Morristown/ Knoxville area Tennessee
Rear Brake rotors
Getting my trailing arms rebuilt and the service offers new rear brake rotors for a additional charge of 40.00 each. I think my existing rotors look good, but wondering what is the correct rotor thickness is suppose to be? I would like to measure with a caliper but don't know what number I should be looking for. What would thickness be on a new pair and is the maximum wear amount?
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
I am not going to dig through my manual because the numbers should be online, but i just looked at some rotors in my stack and the pad doesn't run out to the outer edge. so if they don't have a worn ridge they are probably good unless they are warped.
The other thing is setting the run out to less than .002
http://www.corvettemagazine.com/tech...r-replacement/
The other thing is setting the run out to less than .002
http://www.corvettemagazine.com/tech...r-replacement/
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,754
From: Charlotte NC
BRAND NEW..the rotor is 1.250" thick.
The MINIMUM thickness you can turn it down to is 1.230" ( and this does NOT mean that you can take a lot more material off of one side than the other. They STILL have to be basically the same thickness for heat.)
If it is BELOW 1.215"...they are DISCARDED.
When I do the trailing arms, spindle bearings and brake rotors....I make sure the rotor is WELL in the guidelines. Just taking a new rotor and putting it on a spindle DOES NOT GUARANTEE that it will always work out when it is measured. And that is ASSUMING that the spindle has been indexed and checked to make sure that it is correct sot eh mounting flange where the rotor comes in contact with is true. Because if ti is off enough...it may require shim stock to be installed to get the rotor true....so this does not effect your brake calipers. AND...it does not matter if the calipers have the 'O' ring design seals...because I have seen them leak also. BUT ...making sure your rotor is correct is IMPORTANT if you have the lipped seals in your calipers.
DUB
The MINIMUM thickness you can turn it down to is 1.230" ( and this does NOT mean that you can take a lot more material off of one side than the other. They STILL have to be basically the same thickness for heat.)
If it is BELOW 1.215"...they are DISCARDED.
When I do the trailing arms, spindle bearings and brake rotors....I make sure the rotor is WELL in the guidelines. Just taking a new rotor and putting it on a spindle DOES NOT GUARANTEE that it will always work out when it is measured. And that is ASSUMING that the spindle has been indexed and checked to make sure that it is correct sot eh mounting flange where the rotor comes in contact with is true. Because if ti is off enough...it may require shim stock to be installed to get the rotor true....so this does not effect your brake calipers. AND...it does not matter if the calipers have the 'O' ring design seals...because I have seen them leak also. BUT ...making sure your rotor is correct is IMPORTANT if you have the lipped seals in your calipers.
DUB
Last edited by DUB; Nov 18, 2015 at 06:50 PM.
Drifting
Joined: Jul 2002
Posts: 1,995
Likes: 110
From: Garland Texas
Getting my trailing arms rebuilt and the service offers new rear brake rotors for a additional charge of 40.00 each. I think my existing rotors look good, but wondering what is the correct rotor thickness is suppose to be? I would like to measure with a caliper but don't know what number I should be looking for. What would thickness be on a new pair and is the maximum wear amount?
Minimum thickness is 1.215 .
Mike
Thread Starter
Advanced
Joined: Oct 2015
Posts: 99
Likes: 1
From: Morristown/ Knoxville area Tennessee
Le Mans Master
Joined: Aug 2006
Posts: 7,427
Likes: 1,560
From: mount holly NC
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2019 C3 of Year Finalist (appearance mods)
Drifting
Joined: Jul 2015
Posts: 1,765
Likes: 254
From: Catlett VA
rotors
Getting my trailing arms rebuilt and the service offers new rear brake rotors for a additional charge of 40.00 each. I think my existing rotors look good, but wondering what is the correct rotor thickness is suppose to be? I would like to measure with a caliper but don't know what number I should be looking for. What would thickness be on a new pair and is the maximum wear amount?
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,754
From: Charlotte NC
If you can do this rotor run out check keep your rotors, if not buy the new rotors.
https://www.youtube.com/watch?v=SSxCNbjKi-0
https://www.youtube.com/watch?v=SSxCNbjKi-0
DUB
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
I use beer cans. After draining the can I use a razor knife to make pie shaped wedges that fit between the studs. I've also used aluminum foil. On a surfaced rotor it is possible to get down to effectively "ZERO" run out
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,754
From: Charlotte NC
...back in the day...I used whatever it took to get it right...because this was before the internet and the ease of finding a company that would sell the correct tapered shims.Bottom line... getting it as close to ZERO as possible.
DUB