Operation - Section 3 10/00 OM3023 Page 3-26 Operating Instructions ARSC SYSTEM ACTUATION The retarder control lever (6) allows the operator to apply only the REAR oil-cooled brakes. During nor- mal operation, this lever should be used to control the speed of the truck and to stop the truck instead of using the foot-operated service brake pedal. Use of this lever extends front brake life while maintaining maximum control of the truck. Retarder Control Lever (6, Figure 3-4) The ARSC system is actuated when the system switch is ON. If the set switch on the ARSC set lever is pressed, the travel speed at that moment is set as the downhill travel speed.
If the travel speed exceeds the set downhill speed, the retarder is automatically actu- ated. The set travel speed is displayed on the set travel speed display and is stored in memory. Accelerator Pedal (7, Figure 3-4) The Throttle Pedal (7) is a foot operated treadle pedal which allows the operator to control fuel to the engine to provide engine acceleration. If the accelerator pedal is depressed when the ARSC is being operated, the ARSC is canceled and the speed increases. If the foot brake or retarder control lever are operated when the ARSC is being used, it is possible to reduce the speed or stop the machine.
Brake Pedal (8, Figure 3-4) The Brake Pedal (8) is a foot-operated pedal which activates air-over-hydraulic pressure converters which apply front caliper dry disc brakes and rear oil- cooled wet disc brakes. This pedal should be used when maneuvering in tight places, at the shovel and dump, and when quick stops or severe braking is required. To Set Speed The set range for the travel speed depends on the selection of the shift lever as shown below. When the shift lever is at positions d, 5, 4, 3, L, the set speed range is 10 - 55 km/h (6.2 - 34.2 MPH) The travel speed cannot be set when the shift lever is at N or R.
Ready Light (9, Figure 3-4) When this light is ON, it shows that the travel speed is set and that operation of the ARSC is possible. When it is OFF, the ARSC is not actuated. If the actual travel speed is less that 10 km/h (6.2 MPH) when the setting operation is carried out, 10 km/h is set. It lights up for 3 seconds when the key switch is turned ON to check the bulb. At all other times, the actual travel speed is set. Exhaust Brake Switch (10, Figure 3-4) Making Fine Adjustments Of Set Travel Speed This selects the actuating mode of the exhaust brake. To raise the set travel speed 1 km/h (0.6 MPH), push the ARSC set lever forward once.
To reduce the set travel speed 1 km/h (0.6 MPH), pull the ARSC set lever back once. Position (ON): When the torque converter is in the lock-up range, the exhaust brake is actuated when the operator releases the accelerator pedal Release the ARSC set lever after changing the set travel speed. Position (OFF): The exhaust brake is not actuated when the ARSC is being operated. If the set switch and cancel are operated at the same time, the cancel operation is given priority. When the ARSC is being operated, depress the foot brake or operate the retarder control lever. When the torque converter is in the lock-up range, the exhaust brake is actuated.
If the set switch and tap up are operated at the same time, the tap up operation is given priority. If the set switch and tap down are operated at the same time, the tap down operation is given priority. Lock-Up Pilot Lamp (11, Figure 3-4) This lights up when the torque converter is in the lock-up range and the transmission is in direct drive.