6L80E Master Rebuild Kit with Bonded Pistons and Filter

Master overhaul kit for the GM 6L80E six-speed and its heavier 6L90E sibling, covering 2006-2017 Silverado 1500, Sierra, Suburban, Escalade, Camaro, Corvette, Hummer H2, Cadillac STS and the 2500 HD applications. Manufacturer part number is CXT-GN03820. What separates this from a banner or gasket-and-seal kit is that it ships with the bonded clutch pistons and the friction plates, which are the two things that usually stop a 6L80 rebuild halfway through.

The bonded pistons matter on this transmission. The original 6L80 pistons use a rubber lip bonded to the steel, and heat cycling eventually splits that bond. When it goes, the pack loses apply pressure and you get a slipping or delayed shift that no amount of solenoid work will fix. Replacing them during an overhaul is the difference between a unit that lasts and one that comes back. The kit also carries the frictions for the 1-2-3-4, 3-5-Reverse, 4-5-6 and low-reverse packs, the pan and valve body gaskets, the complete O-ring and sealing-ring set, the front and rear seals, and the pan filter.

Units generally come apart for the 1-2-3-4 and 3-5-Reverse wave plate cracking, which is the classic 6L80 failure and shows as a hard flare or loss of the affected gears, or for converter clutch debris circulating through the valve body. Inspect both wave plates while the unit is open, since the kit will not replace a cracked one. Check the stator support bushings and the TEHCM connector seal at the same time, and clear any stored shift-adapt data after the rebuild so the controller relearns against fresh clutches instead of fighting old values.

Kit weighs 17.26 lb and ships in one box. It does not include the wave plates, hard parts, a torque converter, the TEHCM or the valve body.