The Mercedes 725.0 9-speed automatic transmission, also known as the 9G-Tronic or NAG3, has been in production since 2014 and is used in virtually the entire current Mercedes-Benz lineup, as well as the Aston Martin DBX. Nissan vehicles are equipped with this transmission under the Jatco JR913E designation. Modifications include the AMG SpeedShift TCT 9 and AMG SpeedShift MCT 9.
Small NAG3: W9A400, W9B400, W9X400, W9Y400.
Middle NAG3: W9A500, W9B500, W9S500, W9T500, W9X500, W9Y500.
Large NAG3: W9A700, W9B700, W9S700, W9T700, W9X700, W9Y700.
AMG versions: W9A900, W9B900, W9S900, W9T900, W9X900, W9Y900.
Specifications
| Type | automatic transmission |
| Number of gears | 9 |
| Type of drive | rear / all wheel |
| Engine volume, l | up to 2.0 (Small NAG3) up to 3.5 (Middle NAG3) up to 4.7 (Large NAG3) up to 6.0 (AMG versions) |
| Torque output, Nm | up to 400 (Small NAG3) up to 500 (Middle NAG3) up to 700 (Large NAG3) up to 900 (AMG versions) |
| Recommended oil | ATF MB 236.17 |
| Oil capacity, liter | 9.9 (Small NAG3, Middle NAG3, Large NAG3) 10.9 (AMG versions) |
| Partial replacement, liter | 8.0 (Small NAG3, Middle NAG3, Large NAG3) 9.0 (AMG versions) |
| Maintenance | every 50 000 km |
| Gearbox lifespan, km | ~350 000 km |
| Weight, kg | 95 |
In 2014, a new 9-speed automatic transmission was introduced in the E-Class and CLS-Class. This transmission is designed for vehicles with a longitudinal engine layout and consists of four planetary gear sets, three multi-plate clutches, and three brakes. The automatic transmission is equipped with two oil pumps: an electric one and a mechanical one with a chain drive. Of particular note is the new three-section torque converter with a torsional damper.
In addition to a large number of standard modifications such as the W9A400, W9A500, W9A700, or W9A900, this transmission is also available in numerous hybrid versions: the HW9A500, HW9S500, HW9A700, or HW9T700.
Gear ratios Mercedes 725.0
Using the 2015 Mercedes CLS500 with a 4.7-liter engine as an example:
| Main | 2.47 |
| 1st | 5.503 |
| 2nd | 3.333 |
| 3rd | 2.315 |
| 4th | 1.661 |
| 5th | 1.211 |
| 6th | 1.000 |
| 7th | 0.865 |
| 8th | 0.717 |
| 9th | 0.601 |
| Reverse | 4.932 |
Using
The transmission was installed on:
- Aston Martin DBX 1 (AM8) in 2020 – …;
- Mercedes C-Class W205 in 2016 – 2023; C-Class W206 in 2021 – …;
- Mercedes CLS-Class W218 in 2014 – 2018; CLS-Class C257 in 2018 – 2023;
- Mercedes CLE-Class C236 in 2023 – …;
- Mercedes E-Class W212 in 2014 – 2016; E-Class W213 in 2016 – 2023; E-Class W214 in 2023 – …;
- Mercedes G-Class W463 in 2018 – 2024; G-Class W465 in 2024 – …;
- Mercedes GLC-Class X253 in 2015 – 2022; GLC-Class X254 in 2022 – …;
- Mercedes GLE-Class W166 in 2015 – 2018; GLE-Class W167 in 2018 – …;
- Mercedes GLS-Class X166 in 2015 – 2019; GLS-Class X167 in 2019 – …;
- Mercedes S-Class W222 in 2015 – 2020; S-Class W223 in 2020 – …;
- Mercedes SL-Class R231 in 2016 – 2020;
- Mercedes SLC-Class R172 in 2015 – 2020;
- Mercedes V-Class W447 in 2019 – …;
- Nissan 400Z 7 (RZ34) in 2022 – …;
- Nissan Frontier 3 (D41) in 2021 – …;
- Nissan Titan 2 (A61) in 2019 – 2024.
Disadvantages of the Mercedes 725.0 gearbox
- Owners of early-model automatic transmissions complain of jerking and twitching when shifting. Some respond to firmware updates, some to adaptation, and some to an oil change. There’s currently no definitive solution, and service centers are still shrugging their shoulders.
- Another common problem with this transmission is spontaneous resetting to Neutral. This is caused by damage to the membrane inside the pressure sensor, which requires replacement. Sometimes, replacing the entire control board with a cloned code may be necessary.
- This transmission is very sensitive to lubricant purity, and if you ignore it for too long, the valve body will become clogged with wear debris, causing noticeable jolts or jerks. Occasionally, the gear selector will fail in Neutral and Park.
