Input shaft failure is a common problem in GM 4L60 and 4L60-E units as power levels are increased. Sonnax heavy duty input shaft 77733-10S for 298mm torque converter units is ideal for any high-horsepower street or strip application. The shaft is manufactured from a specially heat-treated steel with very hard outer layers and a more ductile inner core for strength and resistance to fracture. The feedholes are chamfered to reduce stress, and the shaft is further processed by shot peening and deep cryogenic treatment.

• High strength steel ideal for high performance applications
• Shot peened and cryogenically treated for extreme durability
• Unique design protects against failure from stress cracks