“Clearance-sensing slacks adjust to produce a consistent gap between the face of the brake pad and the braking surface of the drum,” said Greg Sturdy, director of wheel end product engineering for Accuride Corp. “Stroke-sensing slacks adjust to produce a consistent distance the pushrod of the brake canister is allowed to move.”
Like any component, if you spec’d your slack adjuster properly, you shouldn’t normally have an issue. However, a key difference between stroke sensing versus clearance sensing could potentially surface. Keith McComsey, director of marketing and customer solutions, wheel-end for Bendix Spicer Foundation Brake, explains:
“If repeated high pressure stops are made, the stroke sensing slack adjuster will sense that the stroke needs to be lengthened due to the high pressure and drum expansion. This condition will cause adjustment, which can result in a dragging brake. The clearance sensing slack adjuster will not see that level of impact on adjustment.”
