GM Service Manual Online
For 1990-2009 cars only

Application

RPO

Specification

Metric

English

Brake Assist Tandem Diaphragm

JC1/JM3

260 mm

10.24 in

Brake Master Cylinder

JC1/JM3

25.4 mm

1 in

Front Disc Brakes

JC1

274.32 x 28.96 mm

10.8 x 1.14 in

Front Disc Brakes

JM3

266.7 x 26.16 mm

10.5 x 1.03 in

Rear Disc Brakes

JC1

294.64 x 20.07 mm

11.6 x .79 in

Rear Drum Brakes

JM3

240.30 x 50.80 mm

9.5 x 2 in