TM 9-2320-386-10 2-82 Change 1 2-32. OPERATION IN EXTREME COLD (Contd) CAUTION Do not apply parking brake. Doing this may cause brakeshoes to freeze to brakedrum resulting in damage to parking brake system. (3) Stop vehicle and engine (para. 2-16). (4) Place chocks in front or behind wheels if parking on a grade. CAUTION Water must be drained from fuel filters, air reservoirs, and fuel tank as soon as possible after operation in extreme cold. Failure to do this may cause water to freeze, resulting in damage to fuel and air sytems. f. After Operation. (1) Perform “after operation” PMCS (table 2-2). (2) Fill fuel tanks as soon as possible. (3) Remove all ice and snow from underside of vehicle, air cleaner intake, and fuel tank. (4) Operate power plant heater, if so equipped, for short standby periods (para. 2-43). If power plant heater will not be used, or is not installed, notify unit maintenance to store batteries in a warm place. 2-33. OPERATION IN ICE OR SNOW a. Before Operation. NOTE If vehicle is to be operated in extreme cold, perform steps in para. 2-32b and 2-32c, then proceed to step (3). (1) Perform “before operation” PMCS (table 2-2). (2) Start engine (para. 2-12). CAUTION Do not attempt operation when only one driving wheel is equipped with tire chains. Doing this may result in damage to tires and powertrain. NOTE Use tire chains on intermediate tires. Remove tire chains as soon as mission allows or when operating on dry pavement. (3) Operation on snow or on ice requires use of tire chains on intermediate driving wheels. (Refer to FM 21-305 for installation of tire chains.) NOTE • Perform step (4) if tire chains are not available and reinflate to normal pressure after operation. • During operation in extreme cold 0° to -65°F (-18° to -54°C), tires must be manually deflated to 18-22 psi (124-152 kPa) (para. 3-9). (4) Place ECU (1) to “S” (sand/mud/snow) setting to deflate tires to 18-22 psi (124-152 kPa) (para. 2-19). (5) Remove wheel chocks from vehicle wheels, if used.