The Ford 9-inch rear axle is one of the most popular differentials in automotive history and the go-to choice for performance applications.

The options are many for upgrading the Forward drum on TH400 racing transmissions.

Prevent pressure drops in high RPM GM TH400 and Powerglide racing applications with this new, specially calibrated high RPM checkball capsule from Sonnax. Testing has shown that OEM checkballs in listed racing applications are unreliable above 5,500 rpm. At higher speeds the checkballs can unseat, resulting in drop of line pressure or converter pressure. There are many variables that effect che...

By the FSC staff Photography courtesy of the manufacturer Whenever things go wrong, racers are always on a pass. Like a fisherman's tale of the one that got away, those mythical incomplete runs are favorite tales to tell around the pit when the racing action dies down for the night. While everyone enjoys a good story about what might have been, it makes for a much better story if your combin...

Confidently running big power through Ford automatics is the new reality for extreme racers on the street and strip. The Smart-Tech direct clutch drum and shaft kit introduced last year by Sonnax is a critical upgrade for any driver pushing the limits of stock AODE, 4R70W components. By popular demand, this revolutionary kit is now available in two gear ratios: the original 2.84/1.55 and new for 2...

The driveline is often the last thing considered when jacking up power to extreme levels but a failure at the track is not the time to learn your slip yoke is the weak link. The new TH400 roller bearing slip yoke from Sonnax takes that worry completely off the table. Proven indestructible in track and street runs plus torture testing in the lab, you can confidently run colossal power from transmis...

Imagine racing a Ford with an automatic that can go head-to-head with the durability of a Powerglide, 400 or 4L80. Confidently running big power through AODE, 4R70W series transmissions is now a reality. Sonnax the most trusted name in transmission innovation is proud to announce the innovative new Smart-Tech direct clutch drum and shaft kit. Proven to handle even the most extreme torque and ...