The 1997 line-up revision saw the introduction of several upgrades, many of which were aimed at increasing engine power outputs.
Thus, most of the previously developed M111 plants were replaced with the new M112 units that head discarded the DOHC layout in favor of a SOHC architecture that was complemented by a 3-valve cylinder head design and twin-spark ignition. The C 230 engine grew in size to 2.4 L while the top-range C280 was re-modeled into a V6 configuration. Diesels also saw a regrowth with the arrival of the OM611 plants, equipped with a common-rail direct injection system jointly developed with Bosch.