MACK T31321, T313L21 and T313LR21 Shifting Instructions CAUTION

Make sur e air essur e least psi and unit operating temperatur e befor e making range shifts. Always start This also applies dynamometer testing. When the truck stationary , NOT shift into range and then start moving the damage the synchr onizer may r esult.

The T313(L)(LR)21 a range - shifted transmission with forward highway speeds and extra gear the and ranges are controlled air - shift range selector

Note: When making a SPLIT SHIFT from gear gear , the splitter switch must not actuated, either down, until the main box NEUTRAL. When making a SPLIT SHIFT the same gear a preselected gear , especially under a heavy load, the splitter will not shift until the driveline torque relieved. This can done depressing the clutch pedal and releasing backing f the throttle and reapplying it. The splitter switch must not actuated, either down, until IMMEDIA TEL Y before the driveline torque When making a RANGE SHIFT , important preselect the range shift. This means that the range selector must moved its next position (up down) BEFORE the gearshift lever moved. Then move the gearshift lever through NEUTRAL the next desired gear the lever passes through the range shift will

Upshift For purposes explaining the shifting procedures through ALL assume that the vehicle has a full load and will climb a slight

Before moving the vehicle, the range selector must range and the splitter switchsplit. With the shift lever NEUTRAL, move the splitter - split (if needed), then the range range (if needed).

Refer the shift pattern and move the shift lever speed gear (LO range,split). Apply accelerator , engage the clutch, and accelerate governed speed. Shift through first, second, third - fourth speed gears, double - clutching between the gears.

T o continue while fourth gear (LO - flip the range selector range then move the shift lever through NEUTRAL fifth gear the lever moves through the range shift will Y are now fifth gear - split (HI Use a combination the splitter and shift lever continue shifting fifth - sixth - sixth - split and until you reach eighth - Remember double - clutch between https://www.truck-manuals.net/mack/