What is the minimum air pressure threshold required for pump shift readiness?

• A. 70 psi
• B. 80 psi
• C. 90 psi
• D. 100 psi

Answer: (B)

Having enough air pressure is what lets the pump shift mechanism operate reliably. The pump shift valve is gas/air–activated, so until the air system is pressurized to a sufficient level, the valve may not move to the pump position or could drop out of it during operation. Setting a minimum threshold ensures there’s both enough air to actuate the shift and a small reserve for safe operation of other air-dependent components.

80 psi is the recommended minimum for pump shift readiness because it provides a safe, practical margin where the shift can engage consistently without needing to wait for higher pressures. pressures like 70 psi are typically too low to guarantee reliable shifting, while 90 or 100 psi are higher than necessary for this readiness check. You aim to confirm the system is at or above 80 psi before shifting to pump mode.