8L45 8-Speed Transmission


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MAXIMUM ENGINE POWER:   308 Hp (230kw)*
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MAXIMUM ENGINE TORQUE:  275 lb-ft (373 Nm)*
8L45 8-Speed GM Powertrain OEM Transmission

8L45 Features
& Specifications

Designed and built by GM, the 8L45 automatic transmission offers increased efficiency and lighter weight compared to the previous 6L45 Hydra-Matic six speed transmissions. With a wide 7.0 overall gear ratio, smaller steps between gears, and numerically higher 4.615 first gear, the 8L45 keeps the engine within the sweet spot of the rpm band for a greater feeling of immediate performance while making the most of its horsepower and torque to optimize performance and efficiency. Advanced features like Automatic Start/Stop, Grade Braking and Driver Shift Control (TAP Shift) are available based on application needs.

maximum engine power: 308 Hp (230kw)*
maximum engine torque: 275 lb-ft (373 Nm)*
maximum gearbox torque: 406 lb-ft (550 Nm)
gear ratios: M5N
first: 4.615
second: 3.038
third: 2.065
fourth: 1.658
fifth: 1.259
sixth: 1.000
seventh: 0.849
eighth: 0.658
reverse: 3.928
maximum shift speed: 7500 RPM
maximum vehicle weights: Up to GCVW 12,000 lbs. (5,443 kg)*
range selector quadrants: 5 position (P, R, N, D, M) Protected for 6 position (P, R, N, D, M, L
case description: 2-piece Main, bell integrated with main case
case material: Die cast aluminum
shift pattern: 2 on-off solenoids
shift quality: 6 variable force solenoids. One for each clutch and one for TCC
torque converter clutch: Variable Force Solenoid ECCC, 2 path, turbine damper
converter size: 238 mm
fluid type: DEXRON™ High Performance ATF
fluid capacity: 10.8L*
transmission weight: 80 kg (176 lb)*
pressure taps available: C12345R Clutch
assembly site: Toledo, OH and Silao, Mexico
*Based on 2020 Chevrolet Colorado Z71 2WD Crew Cab, Short Bed