Drive Trainer / Automatic Transmissions
 

Allison AT Series Road Test Checklist

Neutral Start

Confirm the selector lever aligns with the mark indicating each range including N (Neutral) and P (Park)
Confirm proper function of neutral safety switch - starter should only operate when selector lever is in N or P

Instruments

Confirm proper function of all instruments associated with the transmission, including the speedometer & transmission oil temperature gauge

Parking Brake

Confirm proper function of the application and release of the parking brake
Confirm the brake is not dragging to heating up while released
Confirm the brake is fully applied before the lever reaches full travel

Power Takeoff (PTO)

Refer to the PTO owner’s manual or the vehicle’s manufacturer’s instructions to ensure proper function

No-Load Governed Speed

Confirm the no-load governed speed of the engine
If necessary, adjust the governor to meet the no-load governed speed (spec available through vehicle manufacturer

Shift Sequence

While driving the vehicle check the wide-open throttle shift points. If adjustment is needed refer to the respective AT service manual
        1-2 upshift occurs within 400 rpm of full load governed speed
        2-3 upshift occurs within 300 rpm of full load governed speed
        3-4 upshift occurs within 200 rpm of full load governed speed

Retarder

Confirm proper function at 50 percent to 100 percent apply
Confirm the retarder enable switch turns off the retarder
Confirm the retarder only applies at closed throttle
Confirm low speed cutoff switch turns off retarder in first range
Confirm the retarder temperature indicator increases rapidly when retarder is applied
Confirm the brake lights come on when retarder is applied

Transmission Fluid

Confirm correct fluid level in N (Neutral) and P (Park)
Confirm there are no leaks
Warm transmission and perform a “hot” fluid level check. Ensure vehicle is on a flat surface and transmission in N or P

Other Items

Perform a stall check
Confirm quality of shift