Which of the following could lead to pump cavitation?

Which of the following could lead to pump cavitation?

• A. Incorrect transmission fluid
• B. Clogged transmission vent
• C. Elevated fluid temperature
• D. High fluid level

Answer: (B)

Cavitation in a pump happens when the pressure at the suction side drops below the fluid’s vapor pressure, causing tiny bubbles of vapor to form and then collapse as flow continues. In an automatic transmission, the vent is there to let air escape from the transmission housing as fluid moves. If that vent becomes clogged, air cannot escape or enter properly, and the suction side can develop a vacuum as the pump pulls fluid. That drop in pressure creates the conditions for vapor bubbles to form, leading to cavitation. Other factors aren’t as direct for triggering cavitation: using the wrong transmission fluid mainly affects lubrication and flow characteristics, a high fluid level doesn’t typically create the vacuum needed for cavitation, and while higher temperature does raise vapor pressure (which can contribute to cavitation risk), the clogged vent is the most direct and common cause in this scenario.

Cavitation in a pump happens when the pressure at the suction side drops below the fluid’s vapor pressure, causing tiny bubbles of vapor to form and then collapse as flow continues. In an automatic transmission, the vent is there to let air escape from the transmission housing as fluid moves. If that vent becomes clogged, air cannot escape or enter properly, and the suction side can develop a vacuum as the pump pulls fluid. That drop in pressure creates the conditions for vapor bubbles to form, leading to cavitation.

Other factors aren’t as direct for triggering cavitation: using the wrong transmission fluid mainly affects lubrication and flow characteristics, a high fluid level doesn’t typically create the vacuum needed for cavitation, and while higher temperature does raise vapor pressure (which can contribute to cavitation risk), the clogged vent is the most direct and common cause in this scenario.