Question 1005 · Truck theory test
The diff-lock has been engaged to enable a truck to move off on a slippery road surface. When should the driver disengage it?
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Correct answer
As soon as the truck is underway.
Official explanation
A driving axle is fitted with a differential, which allows the wheels on either side to rotate at different speeds, so that the vehicle can negotiate bends and corners. The purpose of a diff-lock is to cause the wheels to rotate at the same speed, and this is used when extra traction is required, for example if the vehicle is stuck in mud or snow. The diff-lock should be used only at low speed and should be disengaged as soon as possible.
- Topic
- Control of vehicle · Controlling Vehicle Stability
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