Section 39-21-53 - Retractable axle control requirements1. For a motor vehicle manufactured after July 31, 2005, variable load suspension or retractable axles, or both, raised or lowered by air, hydraulic, or other pressure must have the lock or pressure regulator valve, or both, positioned outside the cab and inaccessible from the driver's compartment if there is more than one variable load suspension axle or retractable axle, or a combination of each.2. The control to lift and lower a retractable or variable load suspension axle may be accessible in the driver's compartment, but also may not function as the pressure control device unless allowed by subsection 1.