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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"

  • Taper or Barrel Shape Maximum Dimension

0.25 mm

0.010"

Brake Linings

  • Replacement Thickness

6.35 mm

0.25"

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

  • Air Brake Chamber Type 16

44.4 mm

1.75"

  • Air Brake Chamber Type 20

44.4 mm

1.75"

  • Air Brake Chamber Type 24

44.4 mm

1.75"

  • Air Brake Chamber Type 30

50.8 mm

2.00"

Brake Shoe

  • Brake Shoe Anchor Pin Hole Diameter (16.5" Brake Shoe Only)

25.62 mm

1.009"

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

325 mm

12.779"

Air Drum Brake Component Specifications Front Brakes

Information

Brake Shoe - 381 x 102 mm (15" x 4")

Brake Shoe - 419 x 127 mm (16.5" x 5")

Air Brake Automatic Slack Adjuster (Distance Between Pivot Points)

140 mm (5.5")

140 mm (5.5")

Air Brake Chamber Clevis Setup

72 mm (2.83")

72 mm (2.83")

Brake Lining Thickness

19.1 mm (0.75")

19.1 mm (0.75")

Brake Lining Width

102 mm (4")

127 mm (5")

Manufacturer

Rockwell

Rockwell

Type

Q Plus ™

Q Plus ™

Air Drum Brake Component Specifications Rear Brakes

Information

Brake Shoe - 419 x 178 mm (16.5" x 7")

Brake Shoe - 419 x 178 mm (16.5" x 7")

Air Brake Automatic Slack Adjuster (Distance Between Pivot Points)

140 mm (5.5")

152 mm (6")

Air Brake Chamber Clevis Setup

68.5 mm (2.69")

68.5 mm (2.69")

Brake Lining Thickness

19.1 mm (0.75")

19.1 mm (0.75")

Brake Lining Width

178 mm (7")

178 mm (7")

Manufacturer

Rockwell

Rockwell

Type

Q Plus ™

Q Plus ™