GM Service Manual Online
For 1990-2009 cars only

Air Drum Brake Component Specifications Dimensional

Application

Specification

Metric

English

Brake Drums

  • Maximum Discard Diameter

Marked on Brake Drum

  • Out-of-Round Maximum Dimension

0.38 mm

0.015 in

  • Taper or Barrel Shape Maximum Dimension

0.25 mm

0.010 in

  • Brake Linings
  • Replacement Thickness

6.35 mm

0.25 in

Pushrod Stroke Dimensions Maximum Allowable Stroke at 550-620 kPa (80-90 psi)

  • Air Brake Chamber Type 16

44.4 mm

1.75 in

  • Air Brake Chamber Type 20

44.4 mm

1.75 in

  • Air Brake Chamber Type 24

44.4 mm

1.75 in

  • Air Brake Chamber Type 30

50.8 mm

2.00 in

Brake Shoe

  • Brake Shoe Anchor Pin Hole Diameter 419 mm (16.5 in Brake Shoe Only)

25.62 mm

1.009 in

  • Brake Shoe Anchor Pin to Brake Shoe Roller Hole Span Distance

325 mm

12.779 in