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What does the differential lock (interaxle differential lock) do, and when is it used?
- A.It locks the steering axle straight
- B.It locks the power divider so both drive axles (or wheels, depending on design) turn together, helping get moving on slippery surfaces at low speed
- C.It is for highway cruising speed
- D.It replaces the need for chains in all cases
Correct answer
B. It locks the power divider so both drive axles (or wheels, depending on design) turn together, helping get moving on slippery surfaces at low speed
Why
With an open divider, one spinning wheel or axle can take all the power and leave the truck stuck. Locking it for a low-speed start on snow, ice, or mud shares traction, and it should be disengaged once solid footing and normal speeds return.
Manual topic: Engine Controls - Traction · From the General Knowledge practice bank (GK-371).