Shift Improver Kit for GM TH400/TH375/TH475

The B&M Shift Improver Kit offers a solution for recalibrating your 1965-1987 GM TH400, TH375, and TH475 automatic transmissions. This kit provides two distinct recalibration options, allowing you to tailor the transmission's performance to your needs. It also helps to reduce excess wear on clutches and other internal components by eliminating undesirable shift characteristics. Installation is described as achievable within a few hours for those who carefully follow the provided instructions. It is important to note that this kit does not fit transmissions built after 1987. For vehicles manufactured in 1988 or later that may have had a transmission replacement, it is crucial to check the Julian date stamped on the transmission's identification tag to ensure compatibility.