Brake Boss Wrench

Drivers wrench for backing off over adjusted (tight) S-cam brakes on trucks and trailers.

• Hex sizes are 9/16", 7/16", 12mm and 5/16" square.

• 9/16" for manual adjusters and Bendix ASA-5

• 7/16" for Crewson, Gunite and Haldex ABA

• 12mm for some older model Borg and Beck

• 5/16" square for Meritor (Rockwell)

To adjust Meritor autoslacks, there is a need to back off the adjuster to disengage the anti-reverse pawl or use 105PWL, Pawl Release Tool, available through our online store.