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When is using the inter-axle differential lock (power divider lock) appropriate?
- A.Never, because the lock has no real use
- B.Only while turning sharp corners on dry pavement
- C.For all highway driving to save fuel
- D.For short stretches of poor traction, such as mud, snow, or a slick dock apron, then unlock it on firm ground
Correct answer
D. For short stretches of poor traction, such as mud, snow, or a slick dock apron, then unlock it on firm ground
Why
Locking the power divider forces both drive axles to turn together so one spinning axle does not take all the power. Running locked on dry pavement winds up the drivetrain and wears tires, so it is a temporary traction aid only.
Manual topic: Vehicle Systems - Drive Axles · From the General Knowledge practice bank (GK-120).