ATI is proud to introduce several new Output Shafts to improve the durability of your T400 Transmission. ATI’s new heavy duty 300M Output Shafts feature an extended bearing surface and are gun-drilled to save weight with no governor or speedometer support. This new part is a “Must Have” for your T400 when high horsepower meets heavy weight, or rear gear is numerically low. With today’s technology, making over 1,000 rear wheel HP in your 4,000 lbs streetcar is not uncommon. Combine that with a 30” tire and a 3.54 gear and you have increased the load exponentially, guaranteeing to find the weak link. Maybe your Pro-Mod is making over 4,000 HP with a 1.40 1st gear and 34.5” slick. Do you really want to trust a 40 year old output shaft core in this situation? Now ATI offers a strong affordable option that is easily installed. Available outright or as an upgrade option in your next ATI T400 transmission. Available in three lengths: Standard 9” T400 length (#406026) for 4” tailhousings, 8.5” for special Powerglide length tailhousings (#406026P) and 6” for 4x4 use with no tailhousing (#406026S).