The General Motors 4ET50 (MKA) hybrid automatic transmission was produced at a US plant from 2010 to 2015 and installed in the Chevrolet Volt and Opel Ampera as part of their Voltec hybrid powertrain. A similar, but slightly more powerful, 4ET55 (MKD) transmission was installed in the Cadillac ELR.
Specifications
| Type | hybrid automatic transmission |
| Number of gears | ∞ |
| Type of drive | front |
| Engine volume, l | up to 1.4 |
| Torque output, Nm | up to 370 |
| Recommended oil | ATF Dexron VI |
| Oil capacity, liter | 8.9 |
| Partial replacement, liter | 6.5 |
| Maintenance | every 80 000 km |
| Gearbox lifespan, km | ~250 000 |
Gear ratios GM 4ET50
Using the 2011 Chevrolet Volt with a 1.4-liter engine as an example:
| Main | 2.16 |
| Range | n/a |
| Reverse | n/a |
Using
The transmission was installed on:
- Chevrolet Volt 1 (D1JCI) in 2010 – 2015;
- Opel Ampera A (R12) in 2011 – 2016.
Disadvantages of the GM 4ET50 gearbox
- This is a very rare hybrid automatic transmission, and there is little information about its malfunctions;
- The most well-known problem is the short-lived electric motor bearing of the transmission;
- When it wears out, a loud noise or even a grinding sound is heard from the front wheels;
- The remaining complaints are related to overheating or software failures;
- This transmission is also located quite low and is easily damaged on poor roads.
