In Chrysler 48RE transmissions, the cooler/converter charge circuit is not opened until the pressure regulator valve moves far enough to flow oil. The industry fix of drilling a small orifice between line pressure and cooler circuit ensures flow to the converter/lube circuit, but the hole also increases the converter drain back problem because ATF can drain when the engine is turned off.

Sonnax offers oversized lube regulated pressure regulator valve and line/TV pressure plug kit 22771A-16K that allows rebuilders to salvage worn valve bodies.

• Oversized pressure regulator valve is designed with an internal check valve that allows oil to flow into the converter charge circuit as soon as the vehicle is started
• Internal valve shuts down once line pressure reaches normal levels
• With engine off, the internal check valve prevents fluid from draining out through the orifice, reducing converter drainback
• Includes a matched oversized line/TV pressure plug and pressure regulator spring