Worn bores in the Ford CD4E and Mazda LA4A-EL converter bypass lineup reduce TCC control and cooler flow. This results in bushing or planet failure, reduced converter clutch life from overheating and often results in codes 628/1744/1740. Slippage codes are often generated as the unit comes up to operating temperature. As the temperature rises, valve control becomes poor and excessive clearance creates excessive leakage of converter pressure.

Sonnax oversized bypass clutch control valve kit 73840-BK features a tightly toleranced sleeve and plunger valve to prevent leakage, and an oversized and improved design bypass clutch valve.

• Plunger valve and oversized bypass clutch valve have extended spools for better support and annular grooves to prevent wear due to side-loading
• Lubrication plugs increase lube and converter pressures by tapping into line pressure instead of depleting converter feed
• Plunger sleeve manufactured from highly wear-resistant aluminum
• Hardcoat anodized aluminum valves combat premature wear