Allison Rebuild Kit

The Suncoast Category 3 Allison Rebuild Kit is engineered for LB7/LLY 5-speed transmissions, offering a robust solution for applications exceeding the factory 400 horsepower rating, up to a 700 horsepower capability. It features proprietary clutch components from industry leaders Alto and Raybestos, incorporating C1, C2, C3, and C4 Alto carbonite frictions or Raybestos SCZ frictions. These materials have no center slots and utilize a waffle pattern to aid in oil retention and cooling. The kit includes redesigned apply pistons with improved rubber compounds to withstand higher temperatures, paired with a thicker spring apply plate that prevents the coning and uneven apply surfaces common with OEM plates, thus reducing premature clutch failure. A custom SunCoast apply plate is also integrated to redirect fluid for superior lubrication of frictions from the inside out, ensuring the entire clutch is cooled and preventing the burnt inner half seen in OEM designs. The kit also features an exclusive smart trim clutch control valve and all necessary modifications for the C2 clutch piston to increase its durability. The included triple disc billet torque converter is manufactured in-house with a heavy-duty forged billet steel cover for exceptional lock-up performance. It features custom pump and turbine modifications, tig-welded furnace brazed fins, and proprietary trapezoidal clutch teeth. The kit also replaces the factory flex plate with a one-piece SFI certified billet steel flexplate, eliminating the weakness of stamped steel designs and crucial for high-torque applications. Furthermore, a billet input shaft manufactured from 9310 Vacumelt steel is included to significantly increase torsional fatigue strength, essential for modified vehicles, heavy towing, and high-horsepower applications. A new internal wiring harness with new GM connectors is also part of the kit for reliability, and a strengthened billet C2 clutch hub made from 4140 heat-treated steel with lengthened splines and an increased spline boss diameter is installed for enhanced durability against shock loads and high-stress conditions. The kit also includes a billet P2 planet assembly made from induction-hardened 4140 billet steel, recommended for higher horsepower applications, and a modified SunGear.