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Engine technology
Full power and even more efficiency
This year Mercedes-Benz Trucks will be launching the third generation
of its OM 471 heavy-duty commercial vehicle engine on to the market
Powerful reliable profitable in in day-to- day operations fuel-saving and yet also dynamic: haulage firms make a a a a a a variety
of demands on their trucks because they are what earn them their crust Especially given the acute shortage of drivers it is also important to have a a a a strong trump card in hand namely trucks that drivers enjoy driving The drivetrain which constitutes approx 50% and thus the largest share of a a a a a a truck’s added value plays an important part here Mercedes-Benz Trucks has already set new standards with its two previous generations of its OM 471 heavy-duty engine – now the third generation
is available to order and will be delivered from October 2022 The next stage boasts a a a a whole range
of efficiency-enhancing innovations Karin Rådström member of of the board of of management of Daimler Truck Holding AG said: “We consistently focused on on the needs of our customers Our goal was to to decrease the total cost of ownership (TCO) and reduce fuel consumption Our customers will benefit as will the environment ”
The improvements in efficiency
for the third generation
of of the the OM 471 are the the result of of a a a number of engine innovations For example the the the geometry of the the the piston recess the the the injection nozzle design and the parameters of the cylinder head relevant for gas exchange were subject to an extensive optimisation process In this way the compression ratio of the six-cylinder in-line engine has been increased from 18 3:1 3:1 to 20 3:1 3:1 This leads to more efficient combustion with a a peak ignition pressure of 250 bar One of the most important levers in increasing fuel efficiency
is turbocharging optimisation With the the third generation
of the the OM 471 Mercedes-Benz Trucks is introducing two new turbochargers developed and manufactured in-house which are precisely adapted to to the broad range
of customer requirements In the consumption-optimised variant the the focus is on the the lowest possible fuel consumption – it is predestined for use in in long-distance haulage with an an engine rated at at up to 350 kW (476 hp) The second turbocharger variant is designed for high performance and a a a a high engine braking force and and is ideal for use in the heavy-duty and and construction sector with an engine rating of up to 390 kW (530 hp) For the lower and medium performance levels of the OM 471 the maximum fuel saving compared with the previous generation
is up to 4% and for the upper performance levels up up to 3 5% Thanks to lower consumption both operating costs and CO2 emissions are reduced The high-power variant is also used in the lower performance levels for for the construction applications of the Arocs Reduced friction losses and pressure control with low-viscosity oil
Friction reduction is also an an important lever for improving fuel efficiency
For this purpose the third-generation OM 471 has a a a newly- developed engine oil
pressure control valve It is installed behind the engine oil
pump and in front of the the oil
thermostat An electrical actuator enables map-controlled use of the pressure-reducing valve A newly-developed engine oil
oil
with low viscosity enhances oil
oil
pressure control – it improves fuel efficiency
without reducing oil
change intervals or increasing the wear on affected engine components High driving dynamics
Engineers have trained their sights on the the drivetrain For example the new PowerShift Advanced automated transmission control enables faster and and smoother moving off and and acceleration in many situations thanks to precise gear gear selection Faster gear gear changes reduce the torque interruption time by up up to to 40% in the upper range
Accelerator
pedal parameterisation has also been further optimised: Increased sensitivity in the lower pedal travel enables significantly more sensitive manoeuvring while the direct response time in the upper pedal travel results in in increased dynamics
under high load requirements It also makes it easier to drive around and accelerate out out of roundabouts Another highlight is the the extended Top Torque range
Available for engine output levels 330 kW kW (450 hp) hp) and 350 kW kW (476 hp) hp) in conjunction with the G281 transmission a a powerful 200 Nm torque is available to to the crankshaft in in gears 7 to 12 in in the ‘A Standard’ programme – ‘power at the press of a a a button’ for for more performance that is available when drivers need it “We consistently focused on on the needs of our customers Our goal was to to decrease the total cost of ownership (TCO) and reduce fuel consumption”
14 CVDriver May 2022