As part of the DAF Advanced Transport Efficiency programme, a large number of enhancements have been made to the successful 12.9-litre PACCAR MX engine. The engine, known for its high level of reliability, excellent performance and market-leading fuel efficiency, is supplied in the popular DAF CF85 and XF105 models.
While optimising fuel consumption, DAF first focused on measures that would create significant improvements when trucks are travelling with a partial load — after all, this is the case, on average, 80% of the time. The enhancements to the PACCAR MX engine result in fuel consumption improving by up to 3% and a reduction in CO2 emissions, depending on how the truck is used.
Encapsulated exhaust manifold unit
DAF is the first in the truck industry to use thermal encapsulation not only for the turbo charger, but also for the exhaust manifold unit. This results in even better air management by providing higher turbo efficiency, and therefore more efficient combustion.
The models of the PACCAR MX engine with 265 kW/360 hp, 300 kW/410 hp and 340 kW/460 hp use new pistons that have better thermal properties and require less cooling. This means a smaller oil pump is sufficient for maximum efficiency and less friction loss.
Further improvements have been made to the injection angles and engine management system, making the combustion process cleaner, which results in lower emissions.
Further improving fuel efficiency, continuing to reduce CO2 emissions and optimising total cost of ownership — these are the aims of Advanced Transport Efficiency.
Instead of 89 km/hour, the maximum speed in all DAF CF75, CF85 and XF105 models is set at 85 km/hour as standard. In long distance transport, this results in fuel savings of 2 to 3%, which means reduced costs and lower CO2 emissions.
Engine idle shutdown
The 9.2-litre and 12.9-litre PACCAR engines automatically shut down after 5 minutes of idling. As a result, no fuel is wasted, emissions are lower while the truck is waiting to get back on its way, and fuel consumption is reduced by 1.5 litres per hour.
Information on fuel consumption
To challenge the driver to the most efficient driving style, information on the actual and realized fuel consumption is given on the display integrated in the instrument panel. After engine shutdown comprehensive trip fuel information is available for further evaluation.
In addition to a 16-speed gearbox, a new, lighter, manual 12-speed gearbox is available. This allows the driveline to be more effectively tailored to the specific use of the vehicle. What is more, due to the high torque of the PACCAR MX engine, a 12-speed gearbox is often the best option. The new gearbox now also offers the option of Direct Drive for the version with 375 kW/510 hp, which means less friction and greater efficiency.
The new AS Tronic automated gearbox with a shifting strategy fully optimised for fuel consumption allows the driver to shift gears himself at speeds below 30 km/h and when using the MX Engine Brake; in all other situations the electronics decide the ideal shifting moment to ensure maximum efficiency and the lowest possible fuel consumption.
Lightweight tandem axle
Within its ATe concept, DAF is introducing a new air-sprung tandem axle with single reduction, which has been specially developed for heavy applications requiring additional traction and where off-road driving is limited. The new SR1360T tandem axle is 375 kilograms lighter than the existing tandem axle with hub reduction for off-road applications, and it consumes over 5% less fuel.