A tractor protection valve:

Question

A tractor protection valve keeps air in a tractor or truck air brake system should the trailer break away or develop a bad leak. The valve will close automatically if the pressure drops to an unsafe level.

Accepted Answer

Keeps air in a brake system if there is a bad leak.

Answer

Prevents a truck from being stolen.

Answer

Prevents a trailer from being accidentally released.

A tractor protection valve:

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