e. Mechanical areas including poor welds, soft or cut woodruff keys, sloppy splines and U-joint bearings, and missed
or inadequate lubrication, based on PTO usage.
4. The above rationale points to the wisdom of the commercial dump truck users in advocating that, for dump truck
applications, the PTO should be of the "hot shift" type, be equipped with a PTO controlled engine speed governor system,
and the hydraulic pump should be integrally bolted onto the PTO. The hot shift PTO, as opposed to the current, sliding
gear PTO, provides the benefits of having a constantly engaged driven gear, a multiple plate hydraulic clutch pack which
slips during engagement, and an integrally mounted hydraulic pump without need of driveshaft, U-joints, or slip joint.
While the hot shift PTO and pump features cost more in first cost initially, the result is a much higher truck availability and
reliability and a reduction in the overall cost during the truck's life. The driver merely engages and disengages the PTO
without any specific operational procedure to memorize. The optional engine RPM speed governor permits engine
operation only in the safe range whenever the PTO is engaged.