C5 front rotors on a C4
Thread Starter
Le Mans Master
Joined: Jun 2000
Posts: 6,461
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From: Ypsilanti MI
Cruise-In 10-11-12 Veteran
St. Jude Donor '09-'10-'11-'12-'14
C5 front rotors on a C4
Does anyone know if there are any differences between 13" front rotors for C4s and those for C5s? I am in the middle of a brake job and realized that the part numbers for my new front rotors match up to a C5 not a C4. 
If it makes any difference, I am running 96 grand sport calipers and brackets.
Thanks,
Preston
If it makes any difference, I am running 96 grand sport calipers and brackets.Thanks,
Preston
Le Mans Master
Joined: Jan 2002
Posts: 9,036
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From: Edmonton AB
My C5 rotors are approx 1.25" thick.
The original rotors on this car were 12". However, in
his post here, jim_hewett that indicates that the J55
13" rotors measure approx 15/16" thick
.
The original rotors on this car were 12". However, in
his post here, jim_hewett that indicates that the J55
13" rotors measure approx 15/16" thick
.
Safety Car
Joined: Jan 2004
Posts: 3,783
Likes: 15
From: Northern California
I just installed the 13" GS calipers using Wilwood rotors and they measure 1.1" ( The Wilwoods must be a little thicker than stock). I wouldn't think the C5 and C4 rotors would be the same thickness.
Last edited by GKK; Aug 2, 2008 at 07:11 PM.
Thread Starter
Le Mans Master
Joined: Jun 2000
Posts: 6,461
Likes: 5
From: Ypsilanti MI
Cruise-In 10-11-12 Veteran
St. Jude Donor '09-'10-'11-'12-'14
These are ACDelco rotors, so I just looked up the images on line, and I don't think they will work. The C5 hat comes up at and angle and then flattens off, but the C4 hat comes up at an angle then has about a 1/4" to 3/8" spacer on top of the hat. I probably didn't describe it very well, but the wheels would be pushed in more and may rub on the calipers due to this difference.
Le Mans Master
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From: Greenwood Indiana
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They don't interchange. I'm pretty sure the 12" & 13" C4 rotors have the same hat depth, but the C5's aren't as deep.
Here is a C4 12" on top and a C5 13" on bottom.
Here is a C4 12" on top and a C5 13" on bottom.
