What does running the engine for at least one minute during a cold transmission check accomplish?

What does running the engine for at least one minute during a cold transmission check accomplish?

• A. To warm the oil
• B. To check battery charge
• C. To clear the fluid system of air
• D. To test the starter

Answer: (C)

Purging air from the hydraulic transmission system. Running the engine for a minute allows the transmission pump to circulate fluid through the lines and cooler, pushing any trapped air out of the system so the lines fill completely with fluid. This ensures the transmission can develop proper hydraulic pressure and engage smoothly, avoiding shifting problems caused by air pockets. Warming the oil happens as a side effect, but the main purpose is to clear air from the fluid system. Checking battery charge or testing the starter isn’t the goal of this step.

Purging air from the hydraulic transmission system. Running the engine for a minute allows the transmission pump to circulate fluid through the lines and cooler, pushing any trapped air out of the system so the lines fill completely with fluid. This ensures the transmission can develop proper hydraulic pressure and engage smoothly, avoiding shifting problems caused by air pockets. Warming the oil happens as a side effect, but the main purpose is to clear air from the fluid system. Checking battery charge or testing the starter isn’t the goal of this step.