Contents inside this Modal are only authorable inside of this page.

The first of its kind in a heavy-duty truck in its class, the all-new available Allison®1 10-speed automatic transmission features closer gear spacing that allows the engine to operate in an optimal range at all times with varying load and terrain conditions. This, combined with fortified components used throughout Sierra Heavy Duty’s driveline, provides maximum torque to the wheels at all times.

1.    Allison is a registered trademark of Allison Transmission, Inc.