Scania recently unveiled a liftable and disengageable tandem bogie (LDTA) option that is available on RB662 and R660 axles. The Swedish truck manufacturer says that while the tag axle is lifted and disengaged, it can result in fuel savings of up to 3% by reducing friction and rolling distance. The LDTA only takes 25 seconds to raise with the turn of a knob, reduces the truck’s turning radius, and allows for a ground clearance of around 70 millimetres (2.8 inches) “with a normal chassis height,” Scania explains.
Scania says this solution is ideal for 6x4 and 8x4 truck configurations that even occasionally haul less than full loads. The LDTA is available with weights of 19, 21, and 26 tonnes (21, 23, and 29 U.S. tons) and can support loads of 9.5, 10.5, and 13 t (10.5, 11.6, and 14 U.S. t), respectively, when the second axle is lifted. The system will also alert the operator if the axle is overloaded and will not allow lifting. A dog-clutch connection makes it possible to disengage the axle and the axle itself can be lifted regardless of travel speed.
A Few Caveats
While the LDTA can help improve fuel efficiency, there are a few caveats to be aware of, including the fact you can’t have the tag axle lowered and have the drive disengaged at the same time. The solution is not available for tridem or hub reduction axles at this time. It also needs to be paired with an air suspension and will add 60 kilograms (132 pounds) to the kerb weight of the vehicle.
“A Highly Desirable Function”
“This is a highly desirable function for customers in a variety of applications, such as construction and timber haulage," says Vincente Connolly, UK sales director for Scania (Great Britain) Limited. "Our engineers have determined that substantial fuel savings are achievable, especially for vehicles which make multiple drops every day and run empty on the return leg. In addition to improved fuel economy, operators also benefit from less tyre wear and increased manoeuvrability. The cost of the unit will rapidly be compensated for by highly positive contribution to our customers’ total operating economy – we expect this option to be included in many truck specifications going forward.”