The RTS 300M Main Shaft is designed as a super high-strength upgrade for performance GM automatic transmissions where the factory shaft can become a weak point under increased power and torque.

Manufactured from high-strength 300M alloy steel, this shaft provides excellent toughness and resistance to twisting and fatigue under severe loads. It is ideal for high-horsepower street, drag and competition applications where increased drivetrain reliability is required.

Designed to suit GM TH400, 4L80E and 4L85E transmissions, the RTS 300M Main Shaft is a direct performance upgrade for demanding transmission builds.

Features:

• Manufactured from high-strength 300M billet steel
• Designed for high-horsepower and high-torque applications (1000 HP+)
• Excellent resistance to twisting and fatigue
• Suitable for performance street, drag and competition use
• Suits GM TH400, 4L80E and 4L85E transmissions