What is the minimum transmission oil temperature?

What is the minimum transmission oil temperature?

• A. -20 °C
• B. -25 °C
• C. -30 °C
• D. -15 °C

Answer: (B)

In cold conditions, transmission oil must still flow enough to lubricate gears and bearings. There is a lower limit where oil viscosity becomes so high that circulation is hindered, leading to excessive wear or damage. The specification sets this threshold at -25 °C, meaning temperatures at or above this value are considered acceptable for starting and running the transmission. Therefore, -25 °C is the minimum transmission oil temperature. Temperatures colder than that, like -30 °C, would be below the limit and not acceptable; temperatures such as -20 °C or -15 °C are warmer than the minimum, so they are within the allowable range but do not represent the minimum.

In cold conditions, transmission oil must still flow enough to lubricate gears and bearings. There is a lower limit where oil viscosity becomes so high that circulation is hindered, leading to excessive wear or damage. The specification sets this threshold at -25 °C, meaning temperatures at or above this value are considered acceptable for starting and running the transmission. Therefore, -25 °C is the minimum transmission oil temperature. Temperatures colder than that, like -30 °C, would be below the limit and not acceptable; temperatures such as -20 °C or -15 °C are warmer than the minimum, so they are within the allowable range but do not represent the minimum.