Th400 Speedometer Gear Calculator, 2L diesel. Oct 1, 2025 · The TH400 (Turbo Hydramatic 400) is a widely popular unit in drag race, off-road, and street builds. Brake in 1st and 2nd. ATI SuperCase recommended over 2000 HP! Can be made PG lenghth at no additonal charge. ATI now has an answer for this market and offers three variations of a 2-speed Turbo 400! OEM cased units are rated to 1800 HP and not intended for heavy weight cars. The TH400 is an aluminum cased three speed automatic transmission that was produced by GM. Find a large selection of reliable TH400 transmissions for your 2WD or 4WD vehicle at Summit Racing. Comprehensive guide to the GM TH400 automatic transmission — specifications, identification, history, and adaptability for Jeep conversions. Transmission Specialties offers many different levels of TH400 transmissions and can be tailored to your specific application with a wide range of premium options, including a TSI SFI-approved two-piece cast aluminum case or an OEM-inspected factory case. Home Transmissions TH400 Transmissions TH400 Transmissions Sort By: FTI Performance TH400 Racing Transmission - Sportsman Transbrake - Level 4 $2,549. l16b, hc7, an, hjz, zvtwuyoo4, fkhw, sthxbf7a8, h74mp, bxod, w1a,