Basic Concept

The 9HP is only 0.24 inches (6 mm) longer than, and weighs 16.5 lbs (7.5 kg) less than, the outgoing six-speed transmission. The compact packaging is achieved by using a number of innovative design features: a new compact hydraulic vane-type pump, two patented dog clutches,^[3] which replace bulkier conventional clutch packs, and a nested gear set.^[2] ZF claims that it is able to save an average of 16% in fuel compared with current 6-speed automatic transmissions. The gear ratio spread is 9.81:1. The transmission has a torque range between 280 and 480 Nm.^[1]

Technical data

More information , ...

Gear Teeth and Ratios[lower-alpha 1]				Planetary Gearset: Teeth[lower-alpha 2]				Count	Total	Avg.
Model Type	Torque Capacity First Delivery · Weight			${\displaystyle {S_{1}}}$[lower-alpha 3] ${\displaystyle {R_{1}}}$[lower-alpha 4]	${\displaystyle {S_{2}}}$[lower-alpha 5] ${\displaystyle {R_{2}}}$[lower-alpha 6]	${\displaystyle {S_{3}}}$[lower-alpha 7] ${\displaystyle {R_{3}}}$[lower-alpha 8]	${\displaystyle {S_{4}}}$[lower-alpha 9] ${\displaystyle {R_{4}}}$[lower-alpha 10]	Brakes Clutches	Ratio Span	Gear Step
Gear ${\displaystyle n}$	R	1	2	3	4	5	6	7	8	9
Step ${\displaystyle i_{n-1}/i_{n}}$	–R : 1		1 : 2	2 : 3	3 : 4	4 : 5	5 : 6	6 : 7	7 : 8	8 : 9
9HP 28	280 N⋅m (207 lb⋅ft)[lower-alpha 11] 2013 · 78 kg (172 lb)			42 110	42 110	91 133	42 86	3[lower-alpha 12] 3[lower-alpha 13]	9.8085	1.3303
Ratio ${\displaystyle i_{n}}$	−3.8049 ${\displaystyle -{\tfrac {3,142,144}{825,825}}}$	4.7001 ${\displaystyle {\tfrac {184,432}{39,325}}}$	2.8419 ${\displaystyle {\tfrac {369,664}{130,075}}}$	1.9094 ${\displaystyle {\tfrac {5,776}{3.025}}}$	1.3818 ${\displaystyle {\tfrac {76}{55}}}$	1.0000 ${\displaystyle {\tfrac {1}{1}}}$	0.8081 ${\displaystyle {\tfrac {34,048}{42,133}}}$	0.6995 ${\displaystyle {\tfrac {6,272}{8,967}}}$	0.5802 ${\displaystyle {\tfrac {76}{131}}}$	0.4792 ${\displaystyle {\tfrac {2,176}{4,541}}}$
Step	0.8095		1.6538	1.4884	1.3818	1.3818	1.2375	1.1553	1.2056	1.2107
9HP 48	480 N⋅m (354 lb⋅ft)[lower-alpha 14] 2013 · 86 kg (190 lb)			42 110	42 110	91 133	42 86	3[lower-alpha 12] 3[lower-alpha 13]	9.8085	1.3303
Ratio	−3.8049	4.7001	2.8419	1.9094	1.3818	1.0000	0.8081	0.6995	0.5802	0.4792
Step	0.8095		1.6538	1.4884	1.3818	1.3818	1.2375	1.1553	1.2056	1.2107
Ratio R & even	${\displaystyle {\tfrac {(S_{1}S_{2}-R_{1}R_{2})(S_{3}+R_{3})(S_{4}+R_{4})}{S_{1}S_{2}R_{3}R_{4}}}}$		${\displaystyle {\tfrac {(S_{1}+R_{1})(S_{3}+R_{3})(S_{4}+R_{4})}{R_{1}R_{3}R_{4}}}}$		${\displaystyle {\tfrac {S_{4}+R_{4}}{R_{4}}}}$	${\displaystyle {\tfrac {S_{3}(S_{1}+R_{1})(S_{4}+R_{4})}{S_{3}(S_{1}+R_{1})(S_{4}+R_{4})+S_{1}R_{3}S_{4}}}}$		8: ${\displaystyle {\tfrac {S_{3}(S_{4}+R_{4})}{S_{4}(S_{3}+R_{3})+S_{3}R_{4}}}}$
Ratio odd	1: ${\displaystyle {\tfrac {(S_{2}+R_{2})(S_{3}+R_{3})(S_{4}+R_{4})}{S_{2}R_{3}R_{4}}}}$		3: ${\displaystyle {\tfrac {(S_{3}+R_{3})(S_{4}+R_{4})}{R_{3}R_{4}}}}$		5: ${\displaystyle {\tfrac {1}{1}}}$	${\displaystyle {\tfrac {S_{3}(S_{2}+R_{2})(S_{4}+R_{4})}{S_{3}(S_{2}+R_{2})(S_{4}+R_{4})+R_{2}R_{3}S_{4}}}}$		${\displaystyle {\tfrac {S_{3}(R_{1}R_{2}-S_{1}S_{2})(S4+R_{4})}{S_{3}(R_{1}R_{2}-S_{1}S_{2})(S_{4}+R_{4})+R_{1}R_{2}R_{3}S_{4}}}}$

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How It Works

An Animated Drive Line Schematic & A Rotational Speeds Nomogram

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 ordinate C4 (carrier of the last planetary gearset RS4) follows closely to those of the actual transmission. Note that elements A and F are labelled interchanged (cf. legend below).

9HP Nomogram

▶️ Interactive Nomogram

This interactive 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 5 permanent coupling on 4 joint ordinates and 3 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 6th ordinate (carrier of the fourth 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 6th ordinate for the 10 gear ratios.

Legend:
A : Dog Clutch (couples r1+s2 with input shaft)
B : Clutch (couples s1 with input shaft)
C : Brake (blocks s1 sun gear)
D : Brake (blocks r2 ring gear)
E : Clutch (couples c3+r4 with input shaft)
F : Dog Brake (blocks s3+s4 sun gears)

Acura

• TLX (V6 models, 2015–2020)
• MDX (2016–2020, non-hybrid models)

Alfa Romeo

• Tonale 2.0T engine

Chrysler

• 200
• Pacifica/Voyager minivan (gasoline version)

Dodge

• Dodge Hornet 2023–2024 2.0

FIAT

• Dobló/RAM Promaster City (2015–2022)
• 500C
• Toro
• Ducato (2020–)

MG

• MG 7 (2023–)

Opel/Vauxhall

• Astra (2020; Diesel Engine)
• Insignia (2020; Diesel Engine)

Honda

• CR-V^[4] (diesel, 2015–2022)
• Pilot (2016–2020 optional, 2021 standard on all trims)
• Avancier/UR-V (2016–, 2.0L turbo)
• Odyssey (2018–19 [standard, 10-speed automatic optional])
• Passport (2019–)
• Ridgeline (2020–)
• Civic (diesel, 2018–2022)

Infiniti

• QX60 (2022–)

Jeep

• Cherokee (KL)
• Renegade
• Compass (MP)
• Gran Commander

Ram Trucks

• ProMaster City
• ProMaster (2022–)

Land Rover

• Range Rover Evoque^[2][5]
• Discovery Sport

Jaguar

• E-Pace

Nissan

• Pathfinder^[6] (2022–)