Bert Transmissions Automatic Transmission Extension Housing

Bert Transmissions & the Automatic Transmission Extension Housing

When it comes to circle track racing drivetrain components, few names carry as much weight as Bert Transmissions. Since 1985, Bert has engineered some of the most respected performance transmission components in the oval track world, and their attention to detail extends all the way to seemingly secondary parts — including the automatic transmission extension housing.

The extension housing (also called a tail housing) is the rearmost structural section of an automatic transmission. It seals and supports the output shaft, guides the driveshaft connection, and plays a critical role in maintaining proper driveline geometry under the brutal forces of circle track competition. A poorly designed or worn housing can allow fluid leaks, misalignment, and excess vibration — problems that end races and destroy drivetrain components. This is precisely why racers who trust Bert for their core transmission unit also look to Bert for the housing components that surround it.

Bert's approach to transmission housings reflects their broader engineering philosophy: minimize weight without sacrificing structural integrity. Their precision-machined housings are manufactured from high-quality aluminum, providing a lightweight yet rigid package that accommodates internal components with exacting tolerances. This is especially important in late model and modified racing, where every rotating component's alignment directly affects power transfer to the rear wheels.

The Bert Ball-Spline Tail Housing is one of the brand's standout innovations in this space. Rather than relying on a traditional slip-yoke arrangement, it eliminates the standard slip-yoke connection and greatly reduces friction in the telescoping action of the driveshaft — a critical advantage when rear suspension travel demands constant, smooth driveshaft movement throughout a race. Less friction means less parasitic loss and improved suspension response, particularly on rough dirt surfaces.

Bert's extension housing solutions are designed to integrate seamlessly with their First Generation and Second Generation transmission platforms, which are used across classes including late model, pro stock, and sprint car racing on both dirt and asphalt. Whether you're rebuilding a competition unit or replacing a damaged housing after a hard night on the track, Bert components are engineered to restore factory-spec alignment and sealing performance.

Explore the full range of Automatic Transmission Extension Housing options available, or visit the complete Bert Transmissions brand page to browse their entire lineup of racing drivetrain components — from bellhousings and flywheels to rebuild kits and specialty fluids.