In the Sprinter’s 2021 update, the existing four-cylinder OM651 and six-cylinder OM642 engines will be replaced by a single four-cylinder, two-litre OM654 engine that complies with Euro VI emissions standards. This engine has aluminium block and head construction, lightweight steel pistons and Nanoslide, iron-carbon cylinder wall coating.
This engine is new for the Sprinter, but has been used in passenger-car and Vito models since 2017.
The OM654 comes in several stages of tune, for front-wheel drive (FWD), rear-wheel drive (RWD) and all-wheel drive (AWD) variants.
FWD models get the new engine in single-turbo form, with either 84kW/300Nm or 110kW/340Nm ratings, coupled to a GD8 manual six-speed box or new nine-speed 9G-Tronic automatic.
RWD models have those two powertrain options, plus a 125kW/380Nm manual-box model and a 125kW/400Nm automatic model. The top-shelf 140kW/450Nm engine, with twin turbochargers, couples to a GD9 manual or 9G-Tronic nine-speed auto.
The new automatic box replaces the current seven-speed 7G-Tronic transmission. Like its predecessor, it is a torque converter type, but it has a much deeper first ratio of 5.354:1, compared with the outgoing box’s 4.377:1. It has three overdrive ratios: 0.865:1, 0.717:1 and 0.601:1, compared with the outgoing transmission’s top overdrive ratio of 0.728:1. Reverse ratio is also deeper, at 4.900:1, compared with 3.416:1.
Final-drive ratios for Australian-market Sprinters weren’t stated, but expect deeper-reduction offerings that should further improve gradeability. Also, the very tall overdrive ratio should improve economy at highway speeds.
All wheel drive changes
Sprinter AWD models will get a 4Matic driveline from September 2021. As is currently the case, the AWD range is based on the RWD models, but the AWD option will be fitted only to 3.5-tonne to 5.0-tonne GVM models powered by the 140kW/450Nm engine and coupled to the 9G-Tronic auto box. There will be no manual-transmission 4Matic Sprinters.
Where the current Sprinter 4x4 uses components produced and fitted by Oberaigner in Austria, a former Mercedes-Benz partner company, the 2021 Sprinter’s transfer case and front differential are from Magna Steyr, who developed the 4Matic system for Mercedes-Benz cars and SUVs.
Mercedes-Benz must be confident that the car-origin 4Matic driveline is strong enough for use in a five-tonne-GVM van or light truck Sprinter.
The Sprinter AWD models will be produced in-house, using volume-built components, so that should see significant price reduction in the AWD option.
The 4Matic system employs a hydraulically-actuated wet clutch pack to distribute fore-aft drive at up to 50 per cent to the front axle. Under normal traction conditions all drive is directed to the rear axle. An electronic control unit monitors front/rear wheel speeds and, if it detects any incipient wheelspin, directs drive to the front axle, within milliseconds.
The 4Matic system is integrated with ESP and 4ETS traction control to aid driving dynamics.
Mercedes-Benz stated that the ride height of the 2021 Sprinter AWD models is increased over the clearance with the current 4x4 system.