This is critical to ensure proper brake function after brake reline or other major brake maintenance is performed

APTA Recommended Procedure:

  • 10 snubs
  • From 20 to 5 MPH
  • At approximately 32% decel or every 500' without stopping
  • After the 10th snub, make 1 complete stop from 20 MPH

Better Methods:

  • 20/20/20 - 20 stops from 20 MPH at 20 PSI, or 40 MPH to 20 MPH ten times
  • The purpose is to gradually raise the brake temperatures, to properly seat all brake components, mate the lining to the brake drum to improve contact and to cure the material
  • Measure brake drum temperature to ensure proper brake function
  • Side to side on same axle should generally be within 25°F
  • Steer to rear axle should be within approximately 50°F. This may vary more due to brake valve specifications, suspension component compatibility and retarder function