High-mileage vehicles with GM TH200 or TH200C transmissions often experience poor line pressure control due to a worn pressure regulator bore. This can result in high cooler pressure as well as converter and/or friction element failure. The hardened steel valve continuously oscillates within the cast-iron pump bore, resulting in wear. Orificed line/balance pressure is then allowed to leak past the valve and exhaust to the sump. This prevents the pressure regulator valve from staying in its normal regulating position. Sonnax pressure regulator valve kit 65912-01K that eliminates these problems.