TM-9-2320-273-10

TRUCK, TRACTOR, LINE HAUL; LIGHT EQUIPMENT TRANSPORTER; TRUCK CHASSIS; MEDIUM EQUIPMENT TRANSPORTER

TECHNICAL MANUAL; OPERATOR’S MANUAL

DECEMBER 2012

TM-9-2320-273-10 - Page 170 of 452

PLACING VEHICLE IN MOTION - CONTINUED

11. For M915 through M920, depress the transmission Air Control Button

(Figure 3, Item 2). The button will lock in the depressed position as long as truck

air pressure is 80 psi or higher. It may be necessary to shift through all gears at

engine idle speed several times to eliminate transmission air leaks, particularly in

cold weather.

CAUTION

For M915 through M920, use of the inhibitor override when

the truck is in motion is prohibited. The shift inhibitor

override should only be used when the vehicle is at a

complete stop.

12. For M915 through M920, select the starting gear ratio using the following as a

guide. Pull up on the selector lever (Figure 3, Item 1) to override the inhibitor.

Suggested starting gears-level hard surfaces:

Empty to 75,000 lb GCVW, 6th gear

75,000 to 105,000 lb GCVW, 4th gear

105,000 to 130,000 lb GCVW, 3rd gear

NOTE

For M915A1, use the 1-5 gear range position for all normal

driving conditions. For information on all gear ranges, refer

to Use of Transmission Gear Ranges M915A1 in this work

package.

13. For M915A1, place transmission control lever (Figure 3, Item 1) in desired gear

range (WP 0005).

Figure 3. Transmission Control Lever.

1

2

1

M915 THROUGH M920

M915A1

TM 9-2320-273-10

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