Transmission Internals

Strengthen, repair, and rebuild your gearbox with replacement and high-performance transmission internals. Whether you're servicing a worn factory daily driver, upgrading shift firmness and line pressure, or building a heavy-duty transmission to hold extreme high-horsepower street, drag racing, diesel towing, or off-road abuse, high-strength internal drivetrain components are vital to prevent gear shear, shaft breakage, and clutch slip.

Explore a comprehensive selection of internal components engineered for automatic, manual, and dual-clutch (DCT) gearboxes. Upgrade your transmission with heavy-duty input and output shafts, forged gear sets, dog engagement conversions, upgraded shift forks, carbon synchronizer rings (synchros), detent springs, planetary gear assemblies, high-friction clutch packs, steel reaction plates, heavy-duty bands, valve body shift kits, transbrake solenoids, and sprags. From direct-fit OEM replacement parts to billet internals built for maximum torque transfer, find everything required to keep your transmission holding power under any condition.