The General Motors 4T45E (or MN5) 4-speed automatic transmission was produced from 2003 to 2011 and was installed with both 4-cylinder and V6 engines up to 3.5 liters. This automatic transmission is best known as the automatic transmission in the Saturn Vue, Pontiac Grand Prix, and Chevrolet Malibu.
Specifications
| Type | automatic transmission |
| Number of gears | 4 |
| Type of drive | front |
| Engine volume, l | up to 3.5 |
| Torque output, Nm | up to 278 |
| Recommended oil | ATF Dexron VI |
| Oil capacity, liter | 12.2 |
| Partial replacement, liter | 6.5 without removing the pallet 8.5 with removing the pallet |
| Maintenance | every 80 000 km |
| Gearbox lifespan, km | ~350 000 km |
| Weight, kg | 78 |
Gear ratios GM 4T45
Using the 2006 Saturn Vue with a 2.2-liter engine as an example:
| Main | 3.63 |
| 1st | 2.960 |
| 2nd | 1.626 |
| 3rd | 1.000 |
| 4th | 0.681 |
| Reverse | 2.130 |
Using
The transmission was installed on:
- Chevrolet Cobalt 1 (GMX001) in 2004 – 2010;
- Chevrolet HHR 1 (GMT001) in 2005 – 2011;
- Chevrolet Malibu 6 (GMX380) in 2003 – 2007;
- Chevrolet Malibu 7 (GMX386) in 2007 – 2008;
- Pontiac G6 1 (GMX381) in 2004 – 2008;
- Pontiac Grand Am 5 (GMX130) in 2003 – 2005;
- Pontiac Grand Prix 8 (GMX367) in 2003 – 2008;
- Saturn Ion 1 (GMX357) in 2005 – 2007;
- Saturn Vue 1 (GMT315) in 2005 – 2007.
Disadvantages of the GM 4T45E gearbox
- This is a fairly reliable automatic transmission, but it is very sensitive to oil levels;
- And, as luck would have it, the transmission is notorious for frequent grease leaks through gaskets and seals;
- You can also encounter corrosion of external wiring due to water getting into the harness;
- Other problems here are related to contamination of solenoids by wear products;
- When combined with V6 engines, the torque converter lockup clutch wears out especially quickly.
