Author Topic: disc rotor wear limit  (Read 15553 times)

Offline preaction

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disc rotor wear limit
« on: July 04, 2015, 05:23:08 PM »
I looked in a 67 shop manual and it lists .810 as a rotor thickness but not a wear limit does anyone remember one and am I missing this info in the shop manual.
8F02R218047-  July 18 1968   Dearborn

Offline jwc66k

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Re: disc rotor wear limit
« Reply #1 on: July 04, 2015, 07:00:13 PM »
You use the same rotors (C5ZZ-11002-B) as the 64-66 Mustangs do and the answer I got from my brake guy was no more than 0.010 inch, aka 0.800 inch. The 66 shop manual has it listed as a 0.002 inch "runout" which is supposed to be the same as wear. There are too many variables not specified in the shop manual. As your brake shop for their opinion.
Jim
I promise to be politically correct in all my posts to keep the BBBB from vociferating.

Offline WT8095

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  • Dave Z.
Re: disc rotor wear limit
« Reply #2 on: July 04, 2015, 08:17:55 PM »
The '67 shop manual also contains the following, but the diagram doesn't make sense. Dimension "A" is listed as "maximum" - seems like it should be a minimum. And dimensions "A" & "B" combined would equal over 1.5 inches - does not correspond to the .810" dimension listed on the specs page. Weird.
Dave Z.

'68 fastback, S-code + C6. Special Paint (Rainbow promotion), DSO 710784. Actual build date 2/7/1968, San Jose.
'69 Cougar convertible, 351W-2V + FMX, Meadowlark Yellow.

Offline preaction

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Re: disc rotor wear limit
« Reply #3 on: July 05, 2015, 09:17:58 AM »
Thank you, it seems odd that theirs a wear value for the drums and not the rotors.
8F02R218047-  July 18 1968   Dearborn

Offline carlite65

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Re: disc rotor wear limit
« Reply #4 on: July 05, 2015, 09:34:39 AM »
is the minimum thickness not cast into the inside rotor surface??
5F09C331248

Offline 67gtasanjose

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Re: disc rotor wear limit
« Reply #5 on: July 05, 2015, 10:25:16 AM »
I looked into this last year and believe I found the answer over on VMF site. I wish I could recall exactly what it was but think it was like .780", not much room from a stock rotor to be turned more than say one time for runout,(warp) if it's grooved, chances are it is no good.
Richard Urch

1967 (11/2/66, S.J.) GTA Luxury Coupe, 289-4V w/Thermactor Emissions, C-4, Int./Ext. Decor +many options

2005 (04/05) GT Premium Convertible, Windveil Blue, Parchment Top w/Med. Parchment interior,  Roush Body Appointments

Offline Smokey 15

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Re: disc rotor wear limit
« Reply #6 on: July 05, 2015, 11:18:33 AM »
 What bothers me is that, with most of the crap repop rotors coming from China, many of them have to be trued in a brake lathe before you can use them because the runout is so poor. It used to be that all you had to do was spray them with brake clean, grease and install the bearings and put them on the car.

Offline preaction

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Re: disc rotor wear limit
« Reply #7 on: July 05, 2015, 11:44:39 AM »
Can anyone identify this rotor, I know the repops are close but different.
8F02R218047-  July 18 1968   Dearborn

Offline Brian Conway

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Re: disc rotor wear limit
« Reply #8 on: July 05, 2015, 12:58:42 PM »
 author=67gtasanjose
I looked into this last year and believe I found the answer over on VMF site. I wish I could recall exactly what it was but think it was like .780", not much room from a stock rotor to be turned more than say one time for runout,(warp) if it's grooved, chances are it is no good.

  Pretty good memory.   Brian
« Last Edit: July 05, 2015, 02:19:50 PM by Brian Conway »
5RO9A GT  4 Spd Built 5/29/65
9TO2R SCJ 4 Spd Built 9/19/68
Owner Driver Mechanic
San Diego, Ca.

Offline Toploader

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Re: disc rotor wear limit
« Reply #9 on: July 05, 2015, 03:39:55 PM »
What bothers me is that, with most of the crap repop rotors coming from China, many of them have to be trued in a brake lathe before you can use them because the runout is so poor.

After a couple of hard brakings you'll have to true them once again  ;D
76A-Y-D2-13H-72-6-6
1965 Californian Built Silver Blue Convertible

Offline Smokey 15

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Re: disc rotor wear limit
« Reply #10 on: July 05, 2015, 03:51:07 PM »
After a couple of hard brakings you'll have to true them once again  ;D
That's true! 

Offline preaction

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Re: disc rotor wear limit
« Reply #11 on: July 05, 2015, 06:49:23 PM »
Thanks Brian it was hard for me to see the inside of the rotor with it on the car.
8F02R218047-  July 18 1968   Dearborn

Offline Bob Gaines

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Re: disc rotor wear limit
« Reply #12 on: July 05, 2015, 08:24:46 PM »
Can anyone identify this rotor, I know the repops are close but different.
it is at the very least older because I it is 2 piece instead of the current one piece aftermarket.
Bob Gaines,Shelby enthusiast, Shelby collector , Shelby concours judge SAAC,MCA,Mid America Shelby

Offline sgl66

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Re: disc rotor wear limit
« Reply #13 on: July 05, 2015, 11:48:00 PM »
Who makes the best repop rotors these days? Checked mine today and they are at .775

or, Brian maybe you want to see those rotors go to good use on my car?
66 GT 6T09K12---- scheduled Oct 14, bucked Oct 13 '65

Offline Bob Gaines

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Re: disc rotor wear limit
« Reply #14 on: July 06, 2015, 01:27:51 PM »
Who makes the best repop rotors these days? Checked mine today and they are at .775

or, Brian maybe you want to see those rotors go to good use on my car?
unfortunityly none are the 2 piece style . The one piece is easily distinguished as after market and non original.
Bob Gaines,Shelby enthusiast, Shelby collector , Shelby concours judge SAAC,MCA,Mid America Shelby