GM 6-Speed 6L90 MYD Hydra-Matic Automatic Transmission
The Hydra-Matic 6L90 (production code MYD) is a six-speed automatic transmission produced by General Motors for use in rear- and rear-biased all-wheel-drive vehicles with a longitudinal powertrain orientation. Developed in-house by General Motors, the Hydra-Matic 6L90 is part of the 6LXX family of fuel-saving, electronically controlled six-speed automatic transmissions that succeeded the 5LXX family.
The modular design of the Hydra-Matic 6L90 (MYD) is shared with variants rated for different torque levels to accommodate various engines and vehicle applications. All versions share a unique output gearset configuration that enables it a wider range of ratios than a conventional planetary gearset automatic transmission. This allows the transmission to be tailored for optimal fuel economy while delivering excellent acceleration traits.
The wide overall ratio spread of 6.04:1 allows a “steep” first gear, as well as a very “tall” overdrive top gear for low-rpm highway cruising.
The modular concept of the Hydra-Matic 6L80 centers on the desire for common components and manufacturing tooling for four different size variants of the six-speed family. All versions use three gearsets: a simple input planetary gearset and two output gearsets, one of which is a compound gearset with three pairs of two pinion gears on the output carrier, one pair meshing with the sun gear and the other with the ring gear.
Performance Algorithm Braking
Performance Algorithm Shifting is available on some applications. Performance Algorithm Shifting (PAS) monitors how assertively the driver is using engine output to determine at what engine speed to upshift or downshift.
Driver Shift Control
Driver Shift Control allows the driver to shift the transmission like a clutchless manual gearbox. Electronic safeguards prevent over-revving should the wrong gear position be accidentally selected.
Advanced Control System
Advances in transmission control modules allow them to exist reliably inside the transmission, where temperatures remain fairly constant compared to a body-mounted module. The transmission and module are assembled together, so no additional steps are necessary during vehicle assembly.
The 6L80’s 32-bit transmission control module (TCM) monitors transmission performance and compensates for normal wear in components such as clutch plates, so transmission performance remains consistent for the life of the transmission.
The 6L90 shares about 75 percent of the parts as the 6L80, although the case of the 6L90 is 35 mm longer than the 6L80 case. The 6L90’s case also accommodates additional fasteners between the transmission and the transfer case for improved driveline noise/vibration performance.
|Type:||Six speed RWD / AWD, electronically controlled automatic overdrive transmission with torque converter clutch. Clutch-to-clutch architecture, with integral Electro / Hydraulic Controls Module|
|Maximum engine power (gasoline, truck):||452 hp (337 kw)|
|Maximum engine power (diesel, truck):||300 hp (223 kw)|
|Maximum engine power (passenger car):||555 hp (414 kw)|
|Maximum engine torque (gasoline, truck):||531 lb-ft (720 Nm)|
|Maximum engine torque (diesel, truck):||520 lb-ft (705 Nm)|
|Maximum engine torque (passenger car):||550 lb-ft (746 Nm)|
|Maximum gearbox torque:||885 lb-ft (1200 Nm)|
|Maximum shift speed:||6200 rpm|
|Maximum Validated Weight (GVW):||15000 lb (6803 kg)|
|Maximum Validated Weight (GCVW):||21000 lb (9525 kg)|
|7-position quadrant:||P, R, N, D, X, X, X (X = available calibratable range position)|
|Case material:||Die cast aluminum|
|Shift pattern:||(2) Three-way on/off solenoids|
|Shift quality:||Five variable bleed solenoid|
|Torque converter clutch:||Variable Bleed Solenoid ECCC|
|Converter size:||300 mm|
|Fluid type:||DEXRON VI|
|Fluid capacity with 300 mm converter:||13.0L (10.8 kg)|
|Pressure taps available:||Line pressure|
|Assembly sites:||GMPT Toledo, Ohio, USA; GMPT Silao, Mexico|
|Available Control Features|
|Multiple Shift Patterns (Selectable)|
|Driver Shift Control (Tap Up / Tap Down)|
|Enhanced Performance Algorithm Shifting (PAS)|
|Selectable Tow / Haul Mode|
|Engine Torque Management On All Shifts|
|Altitude and Temperature Compensation|
|Adaptive Shift Time|
|Automatic Grade Braking|
|OBDII / EOBD|
|Integral Electro/Hydraulic Controls Module (Tehcm)|
|Control Interface Protocol – GMLAN|
|Cadillac CTS-V Sedan, Coupe, Wagon||6.2L V8 LSA Supercharged|
|Chevrolet Camaro ZL1||6.2L V8 LSA Supercharged|
|Chevrolet Express CNG (Cargo, Cutaway)||6.0L V8 Vortec VVT|
|Chevrolet Express LPG (Cutaway)||6.0L V8 Vortec VVT|
|Chevrolet Express (Cargo, Passenger, Cutaway)||6.0L V8 Vortec VVT|
|Chevrolet Express (Cargo, Passenger, Cutaway)||6.6L V8 Duramax|
|Chevrolet Express (Cargo, Passenger, Cutaway) < 10K GVW||4.8L V8 Vortec VVT|
|Chevrolet Express (Cargo, Passenger, Cutaway) > 10K GVW||4.8L V8 Vortec VVT|
|Chevrolet Express (Cargo, Passenger, Cutaway) > 10K GVW||6.0L V8 Vortec VVT|
|Chevrolet Express (Cargo, Passenger, Cutaway) > 10K GVW||6.6L V8 Duramax|
|Chevrolet Silverado HD < 10K GVW Bi-Fuel (CNG)||6.0L V8 Vortec VVT|
|Chevrolet Silverado HD > 10K GVW Bi-Fuel (CNG)||6.0L V8 Vortec VVT|
|Chevrolet Silverado HD < 10K GVW||6.0L V8 Vortec VVT|
|Chevrolet Silverado HD > 10K GVW||6.0L V8 Vortec VVT|
|GMC Savana CNG (Cargo, Cutaway)||6.0L V8 Vortec VVT|
|GMC Savana LPG (Cutaway)||6.0L V8 Vortec VVT|
|GMC Savana (Cargo, Pass, Cutaway) < 10K GVW||4.8L V8 Vortec VVT|
|GMC Savana (Cargo, Pass, Cutaway)||6.0L V8 Vortec VVT|
|GMC Savana (Cargo, Pass, Cutaway)||6.6L V8 Duramax|
|GMC Savana (Cargo, Pass, Cutaway) > 10K GVW||4.8L V8 Vortec VVT|
|GMC Sierra HD < 10K GVW Bi-fuel (CNG)||6.0L V8 Vortec VVT|
|GMC Sierra HD > 10K GVW Bi-fuel (CNG)||6.0L V8 Vortec VVT|
|GMC Sierra HD < 10K GVW||6.0L V8 Vortec VVT|
|GMC Sierra HD > 10K GVW||6.0L V8 Vortec VVT|