Abbyisd TH400 Transmission Tail Housing Seal Kit: Stop Leaks, Restore Performance!​​ Is your GM vehicle with a Turbo 400 (TH400) transmission experiencing leaks around the extension tail housing? This common issue often stems from worn-out seals and bushings. Abbyisd provides the complete solution with our premium Tail Housing Seal Kit. ​​What's Included & Why It Matters:​​ This essential kit contains a precisely engineered gasket, a durable seal, and a critical bushing. Together, these components create a vital barrier where the transmission tail housing meets the extension housing (or transfer case adapter on some applications). A failure in any of these parts can lead to costly transmission fluid leaks, potential damage, and messy drips.