If you are driving a diesel truck up a hill and the vehicle stalls in low gear, what should you do?

When driving a diesel truck that stalls while ascending a hill in low gear, selecting reverse gear is the appropriate action. This choice allows you to control the truck's descent safely and prevent it from rolling back uncontrollably down the hill. Engaging reverse gear effectively uses the engine's compression and braking power to help manage the vehicle's movement.

In the event of stalling on an incline, simply selecting first gear may not provide adequate power to restart and continue moving uphill, especially if the vehicle has lost momentum. Turning off the engine is not advisable as it would eliminate any control over the vehicle's movement and would likely require restarting the engine under potentially hazardous conditions. Accelerating rapidly is unsafe and could lead to loss of control, particularly on a slope, given that the truck is already in a stalled condition.

Selecting reverse gear effectively addresses the immediate concern of controlling the vehicle's movement and ensures safety while assessing further steps to regain power and safely navigate the terrain.