ALLISON-OM1334EN

RANGE SELECTION — AT 500 SERIES AND AT 1500 SERIES

WITHOUT A SECOND NEUTRAL (PARK)

; MT 640, MT(B) 643,

MT 643R, MT(B) 644, MT 647; HT 740, HT 747

Use this to back the vehicle. Completely stop the vehicle before shifting

from a forward range to

(Reverse) or from

(Reverse) to a forward

range. The reverse warning signal is activated when the shift selector is in

this position. Reverse has only one range. Reverse operation also

provides the greatest tractive advantage.

Use this position when you start the engine. If the engine starts in any

other position, the neutral start switch is malfunctioning. Neutral position

is also used during stationary operation of the power takeoff (if your

vehicle is equipped with a PTO).

The transmission will initially attain 1st range and, as vehicle speed

increases, the transmission will upshift to 2nd range, 3rd range, and 4th

range automatically. As the vehicle slows down, the transmission will

downshift to the correct range automatically.

WARNING:

If you leave the vehicle and the engine is running, the

vehicle can move suddenly and you or others could be injured. If you

must leave the engine running, do not leave the vehicle until you:

• Put the transmission in

(Neutral).

..and

• Apply the parking brake and emergency brakes and make sure they are

properly engaged.

..and

• Chock the wheels and take any other steps necessary to keep the

vehicle from moving.

WARNING:

If you let the vehicle coast in

(Neutral), there is no

engine braking and you could lose control. Coasting can also cause

severe transmission damage. To help avoid injury and property damage,

do not allow the vehicle to coast in

(Neutral).

WARNING:

If you just downshift or just use service brakes when going

downhill, you can lose control and cause injury and property damage. To

help avoid loss of control, use a combination of downshifting, braking,

and other retarding devices. Downshifting to a lower transmission range

increases engine braking and helps you to maintain control. The

transmission has a feature to prevent automatic upshifting above the

lower range selected. However, during downhill operation, if engine

governed speed is exceeded in the lower range, the transmission may

upshift to the next higher range. This will reduce braking and could

cause a loss of control. Apply the vehicle brakes or other retarding

device to prevent exceeding engine governed speed in the lower range

selected.

ALLISON AT, MT, HT SERIES ON-HIGHWAY TRANSMISSIONS

OPERATOR'S MANUAL

2000