# List of ZF transmissions

ZF Friedrichshafen AG is a German technology manufacturing company that supplies systems, in particular transmissions for all kind of passenger cars and SUVs, light commercial vehicles such as vans and light trucks, as well as all types of heavy and special vehicles like trucks and buses.
Basically there are two types of motor vehicle transmissions:
* Manual – the driver has to perform each gear change using a manually operated clutch
* Automatic – once placed in drive (or any other 'automatic' selector position), it automatically selects the gear ratio dependent on engine speed and load
Basically there are two types of engine installation:
* In the longitudinal direction, the gearbox is usually designed separately from the final drive (including the differential). The transaxle configuration combines the gearbox and final drive in one housing and is only built in individual cases
* In the transverse direction, the gearbox and final drive are very often combined in one housing due to the much more restricted space available
Every type of transmission occurs in every type of installation.

## Passenger cars and light vehicles
### Manual transmissions
#### 4-speed longitudinal

* S4-12 – Lotus Elite type 14 (optional), Autocars/Reliant Sabra sports
* S4-18 – Bedford Van, Opel Blitz Van
* 4 DS-10 – Transaxle as fitted to the Hanomag F20-F36 and Mercedes L206/L306/L307 FWD Vans
* 4 DS-10/2 – Transaxle as fitted to the Hanomag F20-F36 and Mercedes L206/L306/L307 FWD Vans

#### 5-speed longitudinal

* 5 DS 25 – transaxle as fitted to the Ford GT40 MK1 and MK3, De Tomaso Mangusta, De Tomaso Pantera, Maserati Bora, Abarth SE030, Lancia 037, BMW M1, Michelotti Pura
* S5D 310Z – as fitted to the BMW E36 M3 3.0
* S5D 320Z – as fitted to the BMW E36 328i
* S5-16
* S5-17 - Alvis TD 21, Alvis TE 21, Alvis TF 21, Maserati 3500GT (S5-17-2), Maserati Sebring I and II, Maserati Quattroporte I, Maserati Mistral
* S5-18 – Alfa Romeo Alfa 6, BMW 2002 turbo, Fiat Dino, Fiat 130, Maserati Biturbo, Maserati Quattroporte, Opel Kadett C GTE, Talbot Sunbeam Lotus, Renault Master van
* S5-20 – Maserati Mistral, Maserati Sebring, Maserati Mexico, Maserati Quattroporte I, Mercedes-Benz W112 and Mercedes-Benz W113
* S5-325 – Aston Martin DB5 DB6, Maserati Ghibli, Iso
* S5-24 – 1967–1990 Aston Martin DBS, Maserati Quattroporte III
* S5-31 – 1990–2006
* S5-39 – BMW 3 Series (E46), BMW 5 Series (E39), BMW 7 Series (E38), BMW X5 (E53)
* S5-42 – 1987–1995
* S5-47 – 1995–1997

#### 6-speed longitudinal

* S6-37 – 1998–2015 (BMW 3 Series (E46), 4 Series, 5 Series, 6 Series)
* S6-40 – 1989–1996 (Aston Martin Vantage V550, Lotus Carlton/Omega, Chevrolet Corvette, VN Holden Commodore SS Group A)
* S6-45 – (Jaguar F-Type V6, BMW 135i/235i/335i)
* S6-53 – 1999–Present – (Alfa Romeo Giulia Quadrifoglio, Jaguar S-Type Diesel, Land Rover Discovery 3/4, BMW 5 series E60 530d)
* S6-650 – 1999–2010 (Ford F-Series Super Duty pickup Trucks, GM 2500HD & 3500 pickup trucks)

#### 7-speed longitudinal

* S7-45 – 2011–Present (Porsche 911 applications)

### Automatic Transmissions

3- to 9-Speed :
| Model Gener- ation | Version | Pro- duction Period | Engine Orien- tation | Gear Ratios | Gear Ratios | Gear Ratios | Layout | Layout | Layout | Layout | Cou- pling | Control |
| Model Gener- ation | Version | Pro- duction Period | Engine Orien- tation | 1st Top | Count Span | Step Center | Power Flow | Gear- sets | Brakes | Clutch- es | Cou- pling | Control |
| 3HP 12 | 20 kg⋅m (145 lb⋅ft) | 1965 – 1977 | Longitudinal | 2.5600 1.0000 | 3 2.5600 | 1.6000 1.6000 | S | 2 | 2 | 2 | Torque Converter | Hydraulic |
| 3HP 12 | TBD | 1965 – 1977 | Longitudinal | 2.2857 1.0000 | 3 2.2857 | 1.5119 1.5119 | S | 2 | 2 | 2 | Torque Converter | Hydraulic |
| 3HP 20 | TBD | 1967 – | Longitudinal | TBD 1.0000 | 3 TBD | TBD | S | 2 | 2 | 2 | Torque Converter | Hydraulic |
| 3HP 22 | TBD | 1973 – 1990 | Longitudinal | 2.7331 1.0000 | 3 2.7331 | 1.6532 1.6532 | S | 2 | 3 | 2 | Torque Converter | Hydraulic |
| 3HP 22 | 30 kg⋅m (217 lb⋅ft) | 1973 – 1990 | Longitudinal | 2.4795 1.0000 | 3 2.4795 | 1.5746 1.5746 | S | 2 | 3 | 2 | Torque Converter | Hydraulic |
| 4HP 22 | 380 N⋅m (280 lb⋅ft) | 1980 – 2003 | Longitudinal | 2.7331 0.7281 | 4 3.7539 | 1.5541 1.4106 | S | 3 | 4 | 3 | Torque Converter w/ Lockup | Hydraulic |
| 4HP 22 | 380 N⋅m (280 lb⋅ft) | 1980 – 2003 | Longitudinal | 2.4795 0.7281 | 4 3.4055 | 1.5045 1.3436 | S | 3 | 4 | 3 | Torque Converter w/ Lockup | Hydraulic |
| 4HP 18FL 4HP 18Q | 350 N⋅m (258 lb⋅ft) | 1984 – 1998 | Longitudinal Transverse | 2.5789 0.7424 | 4 3.4737 | 1.5145 1.3837 | S | 3 | 2 | 3 | Torque Converter w/ Lockup | Hydraulic |
| 4HP 14 | TBD | 1987 – 2001 | Transverse | 2.4118 0.7387 | 4 3.2647 | 1.4835 1.3348 | S | 3 | 2 | 3 | Torque Converter | Hydraulic |
| 4HP 24 | 400 N⋅m (295 lb⋅ft) | 1987 – 2004 | Longitudinal | 2.7331 0.7281 | 4 3.7539 | 1.5541 1.4106 | S | 3 | 4 | 3 | Torque Converter w/ Lockup | Hydraulic |
| 4HP 24 | 400 N⋅m (295 lb⋅ft) | 1987 – 2004 | Longitudinal | 2.4795 0.7281 | 4 3.4055 | 1.5045 1.3436 | S | 3 | 4 | 3 | Torque Converter w/ Lockup | Hydraulic |
| 4HP 20 | TBD | 1995 – | Transverse | TBD | 4 TBD | TBD | S | 3 | 2 | 3 | Torque Converter | Hydraulic |
| 4HP 16 | TBD | 2004 – 2008 | Transverse | TBD | 4 TBD | TBD | S | 3 | 2 | 3 | Torque Converter | Hydraulic |
| 5HP 18 | 310 N⋅m (229 lb⋅ft) | 1990 – 1997 | Longitudinal | 3.6648 0.7424 | 5 4.9363 | 1.4906 1.6495 | S | 3 | 3 | 4 | Torque Converter w/ Lockup | Electronic |
| 5HP 19 | 325 N⋅m (240 lb⋅ft) | 1997 – 2002 | Longitudinal | 3.6648 0.7424 | 5 4.9363 | 1.4906 1.6495 | S | 3 | 3 | 4 | Torque Converter w/ Lockup | Electronic |
| 5HP 30 | 560 N⋅m (413 lb⋅ft) | 1992 – 2000 | Longitudinal | 3.5526 0.7865 | 5 4.5169 | 1.4578 1.6716 | S | 3 | 3 | 3 | Torque Converter w/ Lockup | Electronic |
| 5HP 24 | 440 N⋅m (325 lb⋅ft) | 1996 – 2002 | Longitudinal | 3.5714 0.8037 | 5 4.4435 | 1.4519 1.6943 | S | 3 | 3 | 3 | Torque Converter w/ Lockup | Electronic |
| 6HP 26 1st | 600 N⋅m (443 lb⋅ft) | 2000 – 2007 | Longitudinal | 4.1708 0.6911 | 6 6.0354 | 1.4327 1.6977 | P & S | 3 | 2 | 3 | Torque Converter w/ Lockup | Electronic |
| 6HP 19 1st | 350 N⋅m (258 lb⋅ft) | 2000 – 2007 | Longitudinal | 4.1708 0.6911 | 6 6.0354 | 1.4327 1.6977 | P & S | 3 | 2 | 3 | Torque Converter w/ Lockup | Electronic |
| 6HP 32 1st | 750 N⋅m (553 lb⋅ft) | 2000 – 2007 | Longitudinal | 4.1708 0.6911 | 6 6.0354 | 1.4327 1.6977 | P & S | 3 | 2 | 3 | Torque Converter w/ Lockup | Electronic |
| 6HP 28 2nd | 600 N⋅m (443 lb⋅ft) | 2007 – 2014 | Longitudinal | 4.1708 0.6911 | 6 6.0354 | 1.4327 1.6977 | P & S | 3 | 2 | 3 | Torque Converter w/ Lockup | Electronic |
| 6HP 21 2nd | 350 N⋅m (258 lb⋅ft) | 2007 – 2014 | Longitudinal | 4.1708 0.6911 | 6 6.0354 | 1.4327 1.6977 | P & S | 3 | 2 | 3 | Torque Converter w/ Lockup | Electronic |
| 6HP 34 2nd | 750 N⋅m (553 lb⋅ft) | | Longitudinal | 4.1708 0.6911 | 6 6.0354 | 1.4327 1.6977 | P & S | 3 | 2 | 3 | Torque Converter w/ Lockup | Electronic |
| CFT 23 | 230 N⋅m (170 lb⋅ft) | 2003 – 2007 | Transverse | 2.42 0.42 | ∞ (CVT) 5.762 | 1.000 (CVT) 1.008 | S | 1 | — | — | Torque Converter w/ Lockup | Electronic |
| CFT 30 | 310 N⋅m (229 lb⋅ft) | 2004 – 2007 | Transverse | 2.47 0.42 | ∞ (CVT) 5.881 | 1.000 (CVT) 1.019 | S | 1 | — | — | Torque Converter w/ Lockup | Electronic |
| 7DT-45 | 500 N⋅m (369 lb⋅ft) | 2009 – | Longitudinal RR | 3.91 0.62 | 7 6.306 | 1.359 1.557 | S | 7 | 0 | 7 | Dual- Clutch | Electronic |
| 7DT-70 | 780 N⋅m (575 lb⋅ft) | 2010 – | Longitudinal RR | 3.91 0.62 | 7 6.306 | 1.359 1.557 | S | 7 | 0 | 7 | Dual- Clutch | Electronic |
| 7DT-75 | 750 N⋅m (553 lb⋅ft) | 2010 – | Longitudinal | 5.97 0.59 | 7 10.119 | 1.471 1.877 | S | 7 | 0 | 7 | Dual- Clutch | Electronic |
| 8DT-80 | 1,000 N⋅m (738 lb⋅ft) | 2016 – | Longitudinal | 5.966 0.534 | 8 11.172 | 1.412 1.785 | S | 8 | 0 | 8 | Dual- Clutch | Electronic |
| 8DT-55 | 600 N⋅m (443 lb⋅ft) | 2019 – | Longitudinal RR | 4.89 0.61 | 8 8.016 | 1.346 1.727 | S | 8 | 0 | 8 | Dual- Clutch | Electronic |
| 8HP 70 Pilot | 700 N⋅m (516 lb⋅ft) | 2008 – 2011 | Longitudinal | 4.6957 0.6667 | 8 7.0435 | 1.3216 1.7693 | P & S | 4 | 2 | 3 | Torque Converter w/ Lockup | Electronic |
| 8HP 30 1st | 300 N⋅m (221 lb⋅ft) | 2010 – 2015 | Longitudinal | 4.7143 0.6667 | 8 7.0714 | 1.3224 1.7728 | P & S | 4 | 2 | 3 | Torque Converter w/ Lockup | Electronic |
| 8HP 45 1st | 450 N⋅m (332 lb⋅ft) | 2010 – 2015 | Longitudinal | 4.7143 0.6667 | 8 7.0714 | 1.3224 1.7728 | P & S | 4 | 2 | 3 | Torque Converter w/ Lockup | Electronic |
| 8HP 55 1st | 650 N⋅m (479 lb⋅ft) | 2010 – | Longitudinal | 4.7143 0.6667 | 8 7.0714 | 1.3224 1.7728 | P & S | 4 | 2 | 3 | Torque Converter w/ Lockup | Electronic |
| 8HP 65 1st | 650 N⋅m (479 lb⋅ft) | 2010 – | Longitudinal | 4.7143 0.6667 | 8 7.0714 | 1.3224 1.7728 | P & S | 4 | 2 | 3 | Torque Converter w/ Lockup | Electronic |
| 8HP 70 1st | 700 N⋅m (516 lb⋅ft) | 2010 – 2015 | Longitudinal | 4.7143 0.6667 | 8 7.0714 | 1.3224 1.7728 | P & S | 4 | 2 | 3 | Torque Converter w/ Lockup | Electronic |
| 8HP 90 1st | 900 N⋅m (664 lb⋅ft) | 2010 – 2015 | Longitudinal | 4.7143 0.6667 | 8 7.0714 | 1.3224 1.7728 | P & S | 4 | 2 | 3 | Torque Converter w/ Lockup | Electronic |
| 8HP 30 2nd | 300 N⋅m (221 lb⋅ft) | 2014 – 2019 | Longitudinal | 5.0000 0.6400 | 8 7.8125 | 1.3413 1.7889 | P & S | 4 | 2 | 3 | Torque Converter w/ Lockup | Electronic |
| 8HP 50 2nd | 500 N⋅m (369 lb⋅ft) | 2014 – 2019 | Longitudinal | 5.0000 0.6400 | 8 7.8125 | 1.3413 1.7889 | P & S | 4 | 2 | 3 | Torque Converter w/ Lockup | Electronic |
| 8HP 75 2nd | 740 N⋅m (546 lb⋅ft) | 2014 – 2019 | Longitudinal | 5.0000 0.6400 | 8 7.8125 | 1.3413 1.7889 | P & S | 4 | 2 | 3 | Torque Converter w/ Lockup | Electronic |
| 8HP 95 2nd | 900 N⋅m (664 lb⋅ft) | 2014 – Present | Longitudinal | 5.0000 0.6400 | 8 7.8125 | 1.3413 1.7889 | P & S | 4 | 2 | 3 | Torque Converter w/ Lockup | Electronic |
| 8P 45R | 450 N⋅m (332 lb⋅ft) | 2016 – Present | Longitudinal | | 8 4.2000 | 1.2275 TBD | P & S | 4 | 2 | 3 | integrated | Electronic |
| 9HP 28 | 280 N⋅m (207 lb⋅ft) | 2013 – Present | Transverse | 4.7001 0.4792 | 9 9.8085 | 1.3303 1.5007 | P & S | 4 | 3 | 3 | Torque Converter w/ Lockup | Electronic |
| 9HP 48 | 480 N⋅m (354 lb⋅ft) | 2013 – Present | Transverse | 4.7001 0.4792 | 9 9.8085 | 1.3303 1.5007 | P & S | 4 | 3 | 3 | Torque Converter w/ Lockup | Electronic |
| Automatic Transmissions With Components For Hybrid Drive On Request |||||||||||||
| 8HP 76/I 3rd | 900 N⋅m (664 lb⋅ft) | 2018 – Present | Longitudinal | 5.0000 0.6400 | 8 7.8125 | 1.3413 1.7889 | P & S | 4 | 2 | 3 | Torque Converter w/ Lockup | Electronic |
| 8HP 30 3rd | 300 N⋅m (221 lb⋅ft) | 2018 – Present | Longitudinal | 5.2500 0.6400 | 8 8.2031 | 1.3507 1.8330 | P & S | 4 | 2 | 3 | Torque Converter w/ Lockup | Electronic |
| 8HP 51 3rd | 500 N⋅m (369 lb⋅ft) | 2018 – Present | Longitudinal | 5.2500 0.6400 | 8 8.2031 | 1.3507 1.8330 | P & S | 4 | 2 | 3 | Torque Converter w/ Lockup | Electronic |
| 8HP 76/II 3rd | 750 N⋅m (553 lb⋅ft) | 2018 – Present | Longitudinal | 5.5000 0.6400 | 8 8.5938 | 1.3597 1.8762 | P & S | 4 | 2 | 3 | Torque Converter w/ Lockup | Electronic |
| Automatic Transmissions With Integrated, Versatile Component System For Hybrid Drive |||||||||||||
| 8HP 100 4th | 1,000 N⋅m (738 lb⋅ft) | 2022 – Present | Longitudinal | 5.0000 0.6400 | 8 7.8125 | 1.3413 1.7889 | P & S | 4 | 2 | 3 | Torque Converter w/ Lockup | Electronic |
| 8HP 80 4th | 800 N⋅m (590 lb⋅ft) | 2022 – Present | Longitudinal | 5.5000 0.6400 | 8 8.5938 | 1.3597 1.8762 | P & S | 4 | 2 | 3 | Torque Converter w/ Lockup | Electronic |
| ↑ for the applications refer to the individual pages ↑ Differences in gear ratios have a measurable, direct impact on vehicle dynamics, performance, waste emissions as well as fuel mileage ↑ plus 1 reverse gear (unless otherwise specified) ↑ Total Ratio Span (Total Ratio Spread · Total Gear Ratio) ${\tfrac {i_{n}}{i_{1}}}$ A wider span enables the downspeeding when driving outside the city limits increase the climbing ability when driving over mountain passes or off-road or when towing a trailer ↑ Average Gear Step $({\tfrac {i_{n}}{i_{1}}})^{\tfrac {1}{n-1}}$ With decreasing step width the gears connect better to each other shifting comfort increases ↑ Ratio Span's Center $(i_{n}i_{1})^{\tfrac {1}{2}}$ The center indicates the speed level of the transmission Together with the final drive ratio it gives the shaft speed level of the vehicle ↑ P: parallel (using the two degrees of freedom of planetary gearsets to increase the number of gears) · S: serial ↑ Epicyclic gearing (unless otherwise specified) ↑ Front-wheel drive · FL: front longitudinal (german: front längs) ↑ Front-wheel drive · Q: transverse (german: quer), without additional F, as transverse installation only occurs with front-wheel drive (even as part of all-wheel drive) 1 2 3 4 5 6 Lepelletier gear mechanism ↑ planned, but never went into production ↑ Ford Motor Company 2005 – 2007 Ford Five Hundred 2005 – 2007 Mercury Montego 2005 – 2007 Ford Freestyle ↑ Porsche PDK (Porsche Doppelkupplungsgetriebe: Porsche dual-clutch gearbox) 2009 Porsche 911 Carrera 2009 Porsche 997 Carrera and Carrera S 2009 Porsche Cayman 2009 Porsche Boxster See also: https://newsroom.porsche.com/en_US/media-resources/technical-specifications.html 1 2 3 4 5 helical gear ↑ Porsche PDK 2010 Porsche 911 Turbo ↑ Porsche PDK 2009 Porsche Panamera ↑ Porsche PDK 2016 Porsche Panamera 2018 Bentley Continental GT 2019 Aston Martin Valhalla V6 Hybrid Limited Edition ↑ Porsche PDK 2020 Porsche 911 Carrera S Cabriolet (8th gear missing) 2020 Porsche 911 Carrera S 1 2 3 Petrol engines · 1,000 N⋅m (738 lb⋅ft) Diesel engines ↑ developed for racing cars ↑ narrow total ratio span · preferebly for petrol engines, sports cars, and high performance engines · The first-ever BMW XM · Market launch September 2022 The all-new BMW M5 · Market launch June 2024 ↑ wide total ratio span · preferebly for Diesel engines, offroad cars, and low performance engines · Progress and efficiency with added variety: additional drive system variants and innovations for the new BMW 7 Series · Market launch 2022/2023 Alpina XB7 AWD · Technical Data |||||||||||||

## Heavy vehicles

These are for heavy motor vehicles; such as large goods vehicles (trucks), buses, motorcoaches, agricultural machinery, plant equipment (such as earth movers), or specialist military vehicles such as tanks.

### Manual synchromesh transmissions for trucks

TD: Truck transmission with direct drive top gear TO: Truck transmission with overdrive top gear

#### 5-speed & 6-speed (ZF Ecolite)

* ZF S5-35/2 manual transmission
* S 5–42
* ZF S635
* 6 S 700 TO
* 6 S 850 TO
* 6 S 1000 TO

#### 9-speed (ZF Ecomid)

* 9 S 1110 TD
* 9 S 1110 TO
* 9 S 1310 TO

#### 12-speed & 16-speed (ZF Ecosplit)

* 12 S 2130 TD
* 12 S 2330 TD
* 12 S 2833 TD
* 16S 221 OD
* 16 S 1620 TD
* 16 S 1630 TD
* 16S 1685 TD
* 16 S 1820 TO
* 16 S 1830 TO
* 16 S 1920 TD
* 16 S 1930 TD
* 16 S 2220 TO
* 16 S 2220 TD
* 16 S 2230 TO
* 16 S 2230 TD
* 16 S 2320 TD
* 16 S 2330 TD
* 16 S 2520 TO
* 16 S 2530 TO
* 16 S 2730 TO

### Manual synchromesh transmissions for tanks
#### 6-speed

* SSG 76 Aphon
* SSG 77 Aphon

#### 7-speed

* AK 7–200

### Automatic transmissions
#### 2-speed auto

* Busmatic – 1963–1979

#### Ecomat series

* 4, 5 or 6-speed with Hydraulic Retarder and Neutral on Vehicle Stop (4/5/6 HP 500/590/600) – 1980–2002
* 4, 5 or 6-speed with Hydraulic Retarder and Neutral on Vehicle Stop (4/5/6 HP 502/592/602/C) – 1997–2007
* 5, or 6-speed with Hydraulic Retarder and Neutral on Vehicle Stop (5/6 HP 504C/594C/604C) – 2006–2016

#### EcoLife series

* 1st generation 6-speed with Hydraulic Retarder (6APxx0x B/C/BS/SP series) – 2008–2019
* 2nd generation 6-speed with Hydraulic Retarder (6APxx2x B/S series) – 2019–
* Off-Road 7-speed with Hydraulic Retarder (7APxx0x and 7APxx2x (S) series)
* Off-Road 6-speed with Hydraulic Retarder and Power Take-Off (6APxx2x SK series)
References:
8-speed PowerLine :
| Model Gener- ation | Version | Pro- duction Period | Engine Orien- tation | Gear Ratios | Gear Ratios | Gear Ratios | Layout | Layout | Layout | Layout | Cou- pling | Control |
| Model Gener- ation | Version | Pro- duction Period | Engine Orien- tation | 1st Top | Count Span | Step Center | Power Flow | Gear- sets | Brakes | Clutch- es | Cou- pling | Control |
| 8AP 600 T | 600 N⋅m (443 lb⋅ft) | 2017 – Present | Longitudinal | 4.8889 0.6389 | 8 7.6522 | 1.3374 1.7673 | P & S | 4 | 2 | 3 | Torque Converter w/ Lockup | Electronic |
| 8AP 800 T | 800 N⋅m (590 lb⋅ft) | 2017 – Present | Longitudinal | 4.8889 0.6389 | 8 7.6522 | 1.3374 1.7673 | P & S | 4 | 2 | 3 | Torque Converter w/ Lockup | Electronic |
| 8AP 1000 T | 1,000 N⋅m (738 lb⋅ft) | 2017 – Present | Longitudinal | 4.8889 0.6389 | 8 7.6522 | 1.3374 1.7673 | P & S | 4 | 2 | 3 | Torque Converter w/ Lockup | Electronic |
| 8AP 1200 T | 1,200 N⋅m (885 lb⋅ft) | 2017 – Present | Longitudinal | 4.8889 0.6389 | 8 7.6522 | 1.3374 1.7673 | P & S | 4 | 2 | 3 | Torque Converter w/ Lockup | Electronic |
| 8AP 1200 S | 1,200 N⋅m (885 lb⋅ft) | 2017 – Present | Longitudinal | 4.8889 0.6389 | 8 7.6522 | 1.3374 1.7673 | P & S | 4 | 2 | 3 | Torque Converter w/ Lockup | Electronic |
| ↑ Differences in gear ratios have a measurable, direct impact on vehicle dynamics, performance, waste emissions as well as fuel mileage ↑ plus 1 reverse gear (unless otherwise specified) ↑ Total Ratio Span (Total Ratio Spread · Total Gear Ratio) ${\tfrac {i_{n}}{i_{1}}}$ A wider span enables the downspeeding when driving outside the city limits increase the climbing ability when driving over mountain passes or off-road or when towing a trailer ↑ Average Gear Step $({\tfrac {i_{n}}{i_{1}}})^{\tfrac {1}{n-1}}$ With decreasing step width the gears connect better to each other shifting comfort increases ↑ Ratio Span's Center $(i_{n}i_{1})^{\tfrac {1}{2}}$ The center indicates the speed level of the transmission Together with the final drive ratio it gives the shaft speed level of the vehicle ↑ P: parallel (using the two degrees of freedom of planetary gearsets to increase the number of gears) · S: serial ↑ Epicyclic gearing (unless otherwise specified) 1 2 3 4 Automatic Powershift Transmission for Trucks 1 2 higher torque on demand ↑ Automatic Powershift Transmission for Special Vehicles |||||||||||||

#### 12-speed AMT

* AS Tronic – automated manual (AMT) with Hydraulic Retarder – 1997–