The ZF 9-speed automatic transmission for passenger cars with front-transverse engines. Thanks to the modular principle, different starting elements and all-wheel drive applications can be implemented cost-effectively even given the restricted installation space conditions with front-transverse passenger cars. The 9-speed provides value for a variety of applications including distribution trucks, rental and lease trucks, school buses, specialty trucks, and defense vehicles. The Allison 9-Speed model leverages the proven durability of the Allison 2000 Series™ six-speed commercial transmissions, which have accumulated well over 100 billion miles globally. The 9-speed Allison is probably the most shocking option. GM, which used to own Allison (purchased in 1929, sold in 2007), still uses their transmissions; an Allison-built 10-speed is behind the 2020 L5P Duramax diesel. Last year, Allison unveiled a new nine-speed which can be dropped into (among other vehicles) heavy-duty trucks.

9G-Tronic is Mercedes-Benz's trademark name for its nine-speed automatic transmission, starting off with the W9A 700 (Wandler-9-Gang-Automatik bis 700 Nm Eingangsdrehmoment; converter-9-gear-automatic with 516 lb-ft maximum input torque; type 725.0) as core model.

Abstract[edit]

9 Speed Transmission Mercedes

In all applications this transmission is identified as the New Automatic Gearbox Generation Three, or NAG3. Initially it debuted on the E 350 blueTEC in 2013,^[1][2] before launched in the Mercedes-Benz S-Class (W222). It has been expanded to be used in the Mercedes-Benz C-Class (W205) and the sedan and wagon variants of the Mercedes-Benz E-Class (W213). This transmission was later introduced on Mercedes-Benz M-Class (W166) facelift on the GLE 250 d model. V12 engine models continue to use the older Mercedes-Benz 7G-Tronic transmission. By the end of 2018 unsurpassed ratio span among longitudinalautomatic transmissions for passenger cars.

It is also fabricated by Jatco for use in Nissan and Infiniti vehicles.^[3][4]

Specifications[edit]

Basic concept[edit]

Technical and economic progress is reflected in nine forward gears^[a] out of ten main components,^[b][5] compared to 7 forward gears^[c] out of 11 main components^[d] in the direct predecessor. It is fully electronic controlled. Torque converter lock-up can operate in all 9 forward gears.

Gear ratios[edit]

Nomogram[edit]

▶️ Interactive Nomogram
This nomogram is a real geometric calculator exactly representing the rotational speeds of the transmission's 3x4 = 12 internal shafts for each of its 9 ratios (+ reverse), grouped according to their 4 permanent coupling on 3 joint ordinates and 5 independent ordinates. These ordinates are positioned on the abscissa in strict accordance with the proportions of the sun gears' teeth numbers relative to those of their rings. Consequently, the output ratios on the 3rd ordinate (carrier of the third planetary gearset) follows closely those of the actual transmission. This advantageous geometric construction sets us free from Willis' famous and tedious formula, because all calculations are exclusively determined by lengths ratios, respectively teeth numbers on the abscissa for the 4 epicyclic ratios, and of rotational speeds on the 3rd ordinate for the 10 gear ratios.

Legend:
A : Brake (blocks s2 sun gear)
B : Brake (blocks r3 ring gear)
C : Brake (blocks c1 carrier gear)
D : Clutch (couples c3 carrier gear with r4 ring gear)
E : Clutch (couples c1 carrier gear with r2 ring gear)
F : Clutch (couples s1 sun gear with c1 carrier gear)

Applications[edit]

Mercedes models[edit]

Mercedes C-Class[edit]

• 2015–2017 Mercedes-Benz W205 (some models)
• 2018–today Mercedes-Benz W205 (all models)

Mercedes E-Class[edit]

• 2014–2016 Mercedes-Benz W212 (E 350 BlueTec only)
• 2016–today Mercedes-Benz W213 (all models)

Mercedes S-Class[edit]

• 2017–today Mercedes-Benz W222 (all except V12 models)

Non Mercedes-Benz models[edit]

Chevy 9 Speed Transmission Problems

• 2021–present Aston Martin DBX
• 2020 Nissan Titan (Jatco JR913E)

See also[edit]

9 Speed Transmission Fluid Exchange

Notes[edit]

1. ^plus 1 reverse gear
2. ^4 simple planetary gearsets, 3 brakes, 3 clutches
3. ^plus 2 reverse gears
4. ^4 planetary gearsets (Ravigneaux planetary gearset considered as 2), 4 brakes, 3 clutches
5. ^First version with a gear ratio span wider than 9:1 as widest among longitudinal automatic transmissions for passenger cars at that time
6. ^Second version introduced without notice with the Mercedes-Benz E-Class (W213) to reduce the step between gear 4 and 5 below the one of the 7G-Tronic (1.3684:1)

References[edit]

1. ^'New nine-speed automatic transmission in the Mercedes-Benz E 350 BlueTEC: Premiere of the new 9G-TRONIC - Daimler Global Media Site'. Media.daimler.com. Retrieved 2020-01-16.
2. ^'Mercedes-Benz E350 BlueTec gains nine-speed automatic transmission'. Retrieved 22 July 2013.
3. ^'Daimler-Renault-Nissan – The alliance in action'.
4. ^'Fact Sheet:Press Releases and Project Overview Daimler & Renault-Nissan Alliance'(PDF).
5. ^ ^ab'System description'(PDF). documents.epfl.ch. Retrieved 2020-01-16.
6. ^'Der neue Mercedes-Benz SL: Die Legende – jetzt noch dynamischer - Daimler Global Media Site'. Media.daimler.com. Retrieved 2020-01-16.

External links[edit]