The Mercedes 722.9 or NAG2 7-speed automatic transmission has been produced since 2003 and is installed on most of the group’s models, gradually giving way to the 9G-Tronic. All AMG versions are equipped with the SpeedShift MCT modification with a clutch instead of a valve body.
This series includes: 722.3, 722.4, 722.5, 722.6, 722.7, 722.9, 725.0.
Specifications
| Production years | since 2003 |
| Type | automatic transmission |
| Number of gears | 7 |
| Type of drive | all wheel / rear |
| Engine volume, l | up to 3.5 (modification W7X550) up to 5.5 (modification W7A700) up to 6.3 (modification W7B700) |
| Torque output, Nm | up to 550 (W7X550) up to 700 (W7A700) up to 850 (W7B700) |
| Recommended oil | MB ATF 236.15 |
| Oil capacity, liter | 8.6 (W7X550) 8.9 (W7A700) 9.1 (W7B700) |
| Replacing the oil | every 60,000 km (W7X550) every 65,000 km (W7A700) every 70,000 km (W7B700) |
| Replacing the filter | every 60,000 km (W7X550) every 65,000 km (W7A700) every 70,000 km (W7B700) |
| Gearbox lifespan, km | ~200 000 |
Gear ratios Mercedes 722.9
Using the example of a Mercedes C-Class 2015 with a 2.0 liter engine:
| Main | 3.070 |
| 1st | 4.377 |
| 2nd | 2.859 |
| 3rd | 1.921 |
| 4th | 1.368 |
| 5th | 1.000 |
| 6th | 0.820 |
| 7th | 0.728 |
| Reverse | 3.416 |
The transmission was installed on:
- Infiniti Q50 1 (V37) in 2013 – 2020;
- Infiniti Q60 2 (CV37) in 2016 – 2022;
- Infiniti Q70 1 (Y51) in 2015 – 2022;
- Mercedes C-Class W204 in 2007 – 2015; C-Class W205 in 2014 – 2018;
- Mercedes E-Class W211 in 2005 – 2009; E-Class W212 in 2009 – 2016;
- Mercedes M-Class W164 in 2005 – 2011; M-Class W166 in 2011 – 2015;
- Mercedes S-Class W220 in 2004 – 2005; S-Class W221 in 2006 – 2013;
- SsangYong Chairman 2 (W) since 2008.
Disadvantages of the Mercedes 722.9 gearbox
- The most famous problem with this automatic transmission is the failure of the control board.
- Two hard-working solenoids: EPC and TCC are also not reliable.
- Vibrations from aggressive acceleration quickly break the automatic transmission housing bell.
- It is not uncommon to replace the multi-function switch or servo module.
- Other breakdowns can be avoided if you monitor the condition and level of the oil.
