Transtec Overhaul Kit With Pistons for GM 6T40 6T45 Gen 1 2008-2012

Transtec Overhaul Kit With Pistons For GM 6T40 And 6T45 Gen 1 2008-2012

Part Number: K118900G
Catalog Reference: 2568
Transmission Application: GM 6T40 and 6T45
Transmission Generation: Gen 1
Application Range: 2008–2012
Transmission Type: Six-Speed Automatic Transaxle
Kit Type: Overhaul Kit With Pistons

This Transtec overhaul kit with pistons is intended for rebuilding GM 6T40 and 6T45 six-speed automatic transmissions with the Gen 1 design. Use Transtec part number K118900G and catalog reference 2568 to match the correct kit for your transmission rebuild.

The kit combines overhaul sealing and gasket components with bonded pistons for transmission rebuild work. It is intended for repairs in which internal inspection identifies worn, damaged, hardened, leaking, or otherwise unsuitable seals, gaskets, sealing rings, or pistons.

Important Fitment Information

This kit is for Gen 1 6T40 and 6T45 units in the 2008–2012 application range. GM introduced major updates during the 2012 model year, and many later Gen 2 internal components are not interchangeable with earlier Gen 1 components. Confirm the transmission identification, build configuration, and original parts before ordering.

The 6T40 and 6T45 transmission families were used across selected Chevrolet, Buick, GMC, Saturn, Pontiac, Saab, Opel, Vauxhall, Daewoo, and related global-platform vehicles. Do not rely on vehicle year or model alone; match the exact transmission and internal generation.

Installation Guidance

This is an internal transmission rebuild kit and should be installed by a qualified transmission professional or experienced rebuilder. Thoroughly clean the transmission, inspect clutch packs and hard parts, check bushing and bearing condition, verify clutch clearances, and follow the applicable manufacturer service information.

Transmission symptoms such as slipping, flare, delayed engagement, harsh shifts, or fault codes may be caused by multiple hydraulic, electrical, mechanical, valve-body, solenoid, or control-system issues. This kit is not represented as a guaranteed repair for an undiagnosed transmission concern.

Refill the completed transmission using the vehicle manufacturer’s required ATF specification. Lubegard ATF Protectant may be considered when compatible with the specified fluid and used according to its product directions.