GM 6T40 Archives - Transmission Digest
Looking for the cause of repeated 6T40 torque converter failure

The converter clutch was applied just enough to drag but not enough to kill the engine.

6T40 delayed engagements after overhaul

The problem lies in the compensator piston that a generation two clutch housing uses compared to the generation one housing.

Shift Pointers: Reassembling GM pumps with cam failure

For the past several years, GM has used a binary positive displacement vane type pump. The compact design allows for it to be utilized in off-axis applications such as the 8L90 transmission and the third generation 6T40 transmission. Figures 1 (above) through 4 display a view of this style pump in the 6T40 applications. The

Sonnax highlights signal accumulator piston kit for GM 6T40

Sonnax highlights its drop-in signal accumulator piston kit (part number 144740-40K) for signal accumulators in GM 6T40 (Gen. 2 & 3) transmissions. According to the company, this kit allows repair of the valve channel casting without reaming, and the O-ring provides a positive seal against critical pressure loss even in worn bores.

Transmission Tech: GM 6T40 Friction Plates

Ever been confused about 6T40 friction plates? Let Mike Riley unravel some of the mystery.