3-5-R clutches in Ford 6F50, 6F55 and GM first generation 6T70 and 6T75 units are applied in third, fifth and Reverse gears in conjunction with other clutch packs. As the 3-5-R clutch regulator valve oscillates and strokes over time, bore deterioration results, which prevents proper hydraulic control of the 3-5-R clutch pack. This can cause flares, slipping, erratic clutch apply timing, ratio codes, bind-ups, and burnt 3-5-R clutches. Reconditioning the bore and installing Sonnax oversized 3-5-R clutch regulator valve kit 124740-21K restores normal shift operation by re-establishing the hydraulic integrity of the 3-5-R circuit.

• Replaces 1.83 ratio OE valve
• Annular grooves help center valve in bore to reduce future side-load wear
• Hardcoat anodized aluminum valve combats premature wear