Mercedes Turbo

Mercedes Turbos: from the OM602 and OM611 engines of the 1990s to today's M276 and OM654

On a Mercedes, the engine code stamped on the block is the first piece of information you need before ordering a turbo. A single commercial designation — "220 CDI" or "3.0 CDI" — can cover several distinct engine codes, and therefore several incompatible turbo references. The OM 646 is the clearest example: its variants OM 646.951, OM 646.961, OM 646.962, OM 646.963, OM 646.966 cover the 200 CDI and 220 CDI across the Classe A, B, C, E, CLK, CLC and Sprinter, yet each suffix can correspond to a different turbo reference. Reading the full code — suffix included — is essential.

Diesel: the OM6xx family and its variants

The diesel engines covered range from the older OM602.980 (2.9 D, found on the Sprinter and older-generation light commercials) through to the OM654 (220 d 190 hp, codes 654920 / OM654.920), taking in the OM611, OM612, OM642, OM646, OM647, OM651 and the smaller OM607 and OM640. The OM642 3.0 CDI V6 is fitted to a large number of models — Classe E, C, CLS, ML, GL, Classe R, Classe S, Sprinter — with suffixes (OM642.850, OM642.852, OM642.853, OM642.854, OM642.858, OM642.872, OM642.920, OM642.921, OM642.950) that do not necessarily share the same turbo reference. On the Vito, Viano and Sprinter, the OM646 and the OM651 (twin-turbo) appear side by side depending on the model year: checking the full code avoids ordering errors. The Citan has a particular feature: it may be fitted with a K9K of Renault origin (108 CDI / 109 CDI / 180 d), with its own turbo references, unrelated to the OM range.

Petrol: M270, M271, M276 and M278

On the petrol side, the new turbos cover mainly four families. The M270 (M270.910, M270.920, M270921) is fitted to the Classe A 160/180/200, Classe B 160/180/200/220/250, CLA 180/200/220/250 and GLA 220/250; the .910 suffix and the .920 suffix do not share the same turbo reference. The M271 (M271.820, M271.860, M271.861) covers the 200 CGI and 250 CGI versions. The M276 (M276, M276.820, M276.823, M276 DE30 AL) covers the E 400, C 43 AMG and GLC 43 AMG in V6 twin-turbo configuration. The M278 (M278.922, M278.932, M278.928, M 278 DE 46 AL) is the V8 twin-turbo of the Classe S 500 and E 500. On these twin-turbo petrol engines, each turbo (front/rear, left/right) may correspond to a distinct reference: the engine code detail and position are required. All turbos in this collection are sold new, as a direct sale, with no old unit to return.