Valve Body Repair Kit for A340/A341/A343/AW4 Transmissions

The TransGo SK340 SHIFT KIT® Valve Body Repair Kit is engineered for 1985 and newer Toyota, Lexus, Isuzu, Mitsubishi, Hyundai, Kia, and Jeep vehicles equipped with A340, A341, A343, and AW4 series automatic transmissions. This kit targets common transmission issues including rough shifts when cold, soft or lazy shifts, delayed kickdown, Torque Converter Clutch (TCC) slip, and overheating. These problems often stem from wear in the TCC relay boost valve and bushing, which compromises lock-up control and leads to overheating. The SK340 addresses these by recalibrating accumulator springs, the pressure regulator spring, and the orifices in the valve body separator plate. A key component of this kit is a USA-made, hardened steel TCC relay boost valve and bushing. This durable part serves as a direct replacement for the softer aluminum OEM assembly that is susceptible to wear, thereby restoring hydraulic circuit integrity for type two, three, and four valve bodies. The kit contains all necessary components to recalibrate accumulators, separator plate feed orifices, and pressure regulation, leading to improved shifting performance and increased transmission durability. It includes specific springs and spacers for accumulators and pressure regulation, along with a 0.055” drill bit for modifications. This kit fits A340, A341, A343, and Jeep AW4 4-speed transmissions from 1985 onwards, with some exceptions for certain Lexus models.