Input shaft failure is a common problem in GM 4L60-E, 4L65-E, 4L70-E units as power levels are increased. Sonnax heavy duty input shaft 77733-12SB for 300mm torque converter, reluctor-style units is ideal for any high-horsepower street or strip application. The shaft is manufactured from 300M ultra high-strength steel for exceptional toughness and resistance to fracture. It features a revised turbine end spline without an undercut where OE shafts commonly break.

• High-strength 300M steel shaft is more than 2X stronger than OE
• Shot peened for extreme durability
• Unique design protects against failure from stress cracks