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Auxiliary Belt Replacement

Model: Mercedes Classe M W163 - Years 1997-2005
Part: V-belt

The auxiliary belt (or service belt) is driven by the crankshaft pulley and operates the alternator, air conditioning compressor, power steering pump, water pump, and cooling fan via the viscous coupling; it is located at the front, just behind the radiator: it may be necessary to remove both the radiator and the fan to replace the belt; before removing the old belt, take note of the routing around the various pulleys (with a photo or sketch), then loosen the tensioner; check the conformity of the new belt (length and number of grooves), route it through the pulleys, and then tension it using the appropriate tensioner.

Updated on 18 February 2026 by ScegliAuto

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