Tri-Five Chevy TREMEC TKX, Magnum, & A41 4L60E Transmission Kits

Modernize the driveability and performance of your 1955, 1956, or 1957 Chevrolet with our PerfectFit™ Transmission Kits. Specifically engineered for the legendary Tri-Five platform, we offer the industry’s premier overdrive solutions to replace dated factory gearboxes. Choose from the streamlined TKX 5-Speed, the high-torque Magnum 6-Speed, or our smooth-shifting A41 4L60E Electronic Automatic.
 

Our Tri-Five kits are meticulously designed to provide a seamless fit into your classic chassis, delivering significantly reduced cruising RPMs and a transformed driving experience. Whether you have a 150, 210, Bel Air, or Nomad, our systems arrive as a total solution. Each kit features all the high-quality components required for a professional installation that preserves the iconic look of your interior while providing the reliability of a modern drivetrain.