Which B-bodies have 12" brakes

[clemsgn]

I found 3 B-body wagons in the bone yard that seem to have the big brakes, but I want to be sure. The rotors measure about 11-5/8" to 11-3/4". Are these the right ones, or is this what the 11 inch rotors measure out to ? I didn't want to go through all the work of removing them & wasting the cash to find out they were the wrong units. I also took the "Service Parts Identification" decals off of all 3 to check codes. After comparing all the codes, I found they all have JA2 which lists in the code description as "Brake, Heavy Duty Disc Drum" . Is this the correct code for the 12 inch brake option ? I read that all the wagons have it, but is this true ?

Please could someone that knows, chime in !

Much appreciated !!
Regards,

 

[Greasemonkey]

Those should be correct. An easier way to check is the 12" brakes have the 5x5 bolt pattern.

 

[clemsgn]

Thanks

And the 11" have the 5 on 4-3/4" ??

What size wheel studs are used...12" are 1/2" and 11" are 7/16" ??

Thanks,

 

[GN ERGY]

Have the bone yard torch them off for you. I gave the yard guy an extra $5 to cut the old ball joints and tie rod end off for me.
Tarey D.

 

[clemsgn]

GN ERGY, I wasn't refering to the wheel lug nut sizes, I was just trying to make sure I get the right parts. I have no problem doing the work to remove them as this place doesn't do it. I figured if the 12" rotors had the 5" circle, then the 11" may use the 4-3/4". I was just using the stud diameters (and bolt circle)to help me identify the 12" spindles, in relation to the 11".

Thanks again for the help

 

[Greasemonkey]

Yeah, the 11" are 4 3/4. I'm not sure of the stud sizes though.

 

[mygrain]

would the brake/spindle set up from a 1995 chevy police car work?

 

[Red Regal T]

I'm pretty sure all studs for either size rotor are the same. What are you gonna do for wheels if you have 5" bolt pattern? Have different on front and rear?

 

[turbofish38]

All B-body wagons have the 12" rotors as standard. The bolt pattern is 5 X 5" with 1/2" studs. The 11" rotors(on the sedans) can be either 5 X5" or 5 X 4.75", again the 5" will have 1/2" studs and the 4.75" will have 7/16" but only some real oddball models have the 5 X 5" pattern. You are going to have to use the 1LE Camaro rotors for the 12" upgrade. The 12" rotors actually measure out at 11.75 to 11.875.