What Causes Semi-Truck Brake Problems?

Brake problems are the #1 out-of-service violation in roadside inspections. Most are preventable if you know what to look for.

The usual suspects: worn shoes/drums beyond spec, out-of-adjustment slack adjusters, leaking air chambers, frozen S-cams, damaged air lines, and failed ABS modulators.

Listen for hissing at idle (air leak), feel for grabbing or pulling under braking, and look for low air pressure builds. Any of these means schedule brake service before it becomes a citation or a runaway.