DISC 4F1848 - Caterpillar

Due to unequal wheel speeds, torque wind up can occur in the drive line of Articulated Dump Trucks. This locked in torque can be released without warning during disassembly of driveline components.This can cause personal injury.To avoid sudden release of locked in torque, do the following procedure before disassembly of driveline components:
1. Operate the machine with interaxle differential lock disengaged.2. Park the machine on level ground, install the articulation locks and block the rear wheels to prevent the machine from rolling.3. Release the parking brake and use the suspension control manual override lever to completely lower the front suspension. The wheel base will lengthen as the suspension lowers due to the configuration of the suspension frames. On two axle machines with rear suspension, lower the rear suspension in a similar way. Do not lower the rear suspension on three axle machines.4. Apply the parking brake.5. Using a 460mm (18") pry bar inserted between the universal joint and the yoke, attempt to rotate the drive shafts back and forth. If the shafts are free, proceed with the intended work. If the shafts are not completely free, continue with steps 6 thru 8.6. On 4x4 and 6x4 machines, raise one front tire off the ground. On 6x6 machines, raise one front and one rear tire off the ground. Both tires must be off the ground when step 7 is performed.7. With the tire(s) raised, release the parking brake. The raised wheel(s) will turn, releasing the torque wind up from the driveline. When the wheels have stopped, apply the parking brake and lower the wheels to the ground.8. Repeat step 5.