On diesel trucks, especially those that tow, you may hear about an exhaust brake. It is a way to slow the vehicle using the engine so the regular brakes do less work. Here is what an exhaust brake is.
How it works
An exhaust brake places a valve in the exhaust that restricts flow when you lift off the throttle. That back-pressure makes the engine hard to turn, creating strong engine braking that slows the truck - a stronger version of normal engine braking.
Why it matters for towing
On a long downhill with a heavy load, riding the wheel brakes overheats them and risks fade; see why brakes overheat towing and brake fade. An exhaust brake lets the engine hold the truck back so the friction brakes stay cool and ready for real stops.
Exhaust brake vs jake brake
An exhaust brake restricts the exhaust; a compression-release (jake) brake, common on big rigs, releases compressed air at the top of the stroke and is louder. Both use the engine to slow the vehicle, sparing the wheel brakes on descents.
Still need good wheel brakes
An exhaust brake reduces wear but does not replace the friction brakes, which still handle stopping - keep them strong for towing; see best pads for towing. Fit quality pads and hardware.