Where is the gas valve switch of the truck?

The exhaust brake switch of large trucks is generally combined with the wiper, and light trucks do not have this equipment.

Purpose of exhaust brake: It is integrated with the wiper switch. Lift this switch to release the clutch pedal and the accelerator pedal. When the transmission is in a gear other than neutral, the exhaust brake will work. If you want to release the exhaust brake, just press the exhaust brake switch again.

Extended data:

Exhaust braking is widely used in large diesel vehicles. The exhaust pipe of the engine is equipped with a regulating valve, and the pressure of the exhaust stroke is increased by closing the valve, and the braking force is obtained by using the generated negative pressure. Driven by machinery, in most cases, it uses the same power source as the main brake. Usually, the exhaust brake is activated by a manual switch. In order to prevent the engine from stalling when parking and exhaust braking when injecting fuel, the exhaust braking will be released automatically when the accelerator pedal or clutch pedal is depressed. Because the oil is cut off at work, the gasoline car can't be braked by exhaust. The correct use of exhaust brake can greatly reduce the use of service brakes (brakes), thus reducing the wear of brake shoes (or brake discs) and greatly reducing the driving safety risk caused by overheating of brake shoes (or brake discs) during continuous braking.