The lubrication of truck motors does not
function like the splash- lubrication in motor cars. The oil mist would not be sufficient. The gearwheels are broader and the cog pressures are higher because of the substantially higher torque to be transferred. At the
same time the required running performance is, around five- to ten times higher. Thus a pressure circulation lubrication is necessary. An important tip also concerning towing.
How it works
If one removes the mechanism for the clutch operation from the clutch housing, the bulkhead to the gearbox can be seen. Thereby the external casing of the oil pump on the left and also the ends of the three selector
rods on top on the right are visible. This is connected with the face of the countershaft which must, in addition, through the preswitching group, always be driven. The oil is sent to specific bearings through drillings in
the casing. However, gearwheel pairs are lubricated by pipes with spray nozzles which are laid under the lid.
Analog to the automatic gearbox with this pump one can also speak of a primary pump because it is driven by the engine. This lays down the
conditions for possible towing
operations. Shorter, about 10 km and slower towing is probably possible without furher preparation. However, should the towing be longer, and at open road speeds, due to the lack of engine power, the cardan shaft
must be disconnected or the vehicle must be towed backwards with the rear axle raised.