Retarder and intarder: why you need them in the mountains

On a long descent, a truck's service brakes can overheat in a matter of minutes — and then they simply stop working. That is exactly what a retarder and intarder protect against. Here is how they differ and when paying extra for them is worth it.

How it works

Both systems brake without involving the wheel mechanisms. A retarder is a hydraulic or electromagnetic decelerator mounted on the transmission shaft. An intarder works on the same principle but is built into the gearbox (the classic example being the ZF Intarder). On top of that there is the engine brake (EVB, Jake brake), which works through engine compression — it is weaker, but it is fitted on almost everything.

When it is worth it

• The Carpathians, the Balkans, the Alps — regular mountain routes make a retarder effectively mandatory.
• Gross weight of 40+ tonnes: the heavier the rig, the faster the service brakes heat up.
• Savings: pads and discs last 2–3 times longer — the system pays for itself in maintenance.

On flat routes you can get by with the engine brake and avoid paying extra. In the listings of our catalog, the presence of a retarder is shown in the specifications — filter by what fits your runs.