Truck gearbox

Environmental developments

The European Union has made emission laws ever since 1988. These rules are called the Euronorm and there purpose is to make vehicles less harmfull for the environment. During the last 30 years, these laws have been getting stricter to reduce the emissions of passenger and commercial vehicles. The gearbox is an important factor for manufacturers to comply with these laws.
 

Retarder

To reduce the impact on the environment, manufacturers are fitting retarders on there gearboxes. A ZF-intarder for Renault and DAF gearboxes. And a Voith retarder for the Volvo and Renault gearboxes.

There can be different sorts of retarders in trucks. The most common one is the hydraulic retarder. This one works by two discs spinning in opposite direction with hydraulic oil in between. When the retarder is activated the oil builds up pressure which reduces the speed of the discs and therefore the speed of the driveline. The other option a magnetic retarder. This one works with magnetic fields that slow each other down when activated.
 

Smart software

Another development for truck gearboxes is software based. Manufacturers are trying to get the truck running at the right RPM at all times. In doing this the truck will always perform at its best and fuel consumption will be optimal.

Volvo does this with their I-shift gearbox. The software on this gearbox analyses the speed, weight, slope angle and the required amount of torque to decide at what exact moment the truck needs to shift.
 

Dual clutch

In 2014 Volvo launced the first commercial truck with a double clutch gearbox. This technology was designed for racing purposes and is later applied in luxury sports cars. The idea is that one clutch operates the current gear of operation, and that the other clutch will have the next gear ready. The result is extremely fast shifts. Volvo calls it the I-shift Dual Clutch.