Retarders are used to further improve the braking performance on commercial vehicles. Like engine brakes, they are wear-free continuous brakes. Retarders relieve the service brake and increase the active safety and cost-effectiveness of commercial vehicles. Retarders are installed in a commercial vehicle's drive train.

How does a retarder work?

An engine retarder captures the exhaust from the engine and compresses it so that the engine must work harder to push the gas out of the cylinders, and it therefore retards and slows the engine through resistance.

When should you use a retarder?

A retarder is a device used to augment or replace some of the functions of primary friction-based braking systems, usually on heavy vehicles. Retarders serve to slow vehicles, or maintain a steady speed while traveling down a hill, and help prevent the vehicle from "running away" by accelerating down the hill.