8HP45

The perfect increase in efficiency

8HP 8-speed automatic transmission for passenger cars

Innovation by reduction: efficiency, perfected

The new 8HP 8-speed automatic

luxury cars, and in every type of SUV and off-road

transmission, which was designed

vehicle – its revolutionary design is always an

to be more lightweight, sets new

efficient and economical solution.

standards for flexibility, efficiency, and economy. It is an excellent

Although the 8HP features 2 more speeds than the

example of how the power of inno-

extremely successful 6HP, the dimensions have

vation can create a new classic

remained unchanged and the weight was even

design.

reduced by 3 percent to 89 kg (196 lbs.) including oil.

A torque range from 300 to 1000 Nm makes the 8HP the perfect

At the same time, the total transmission ratio spread

partner for all rear-wheel-drive and

of 7.0 ensures that the engine is always in its

all-wheel-drive designs. From the

optimum operating range. This translates into

lower midsize segment to sporty

improved acceleration and reduced fuel

Weight [kg]

consumption.

5HP30 118.5 kg

120

110 6HP32 99.0 kg

5HP24 99.0 kg 100 6HP26 89.0 kg 90

5HP19 79.0 kg

6HP28 91.0 kg 8HP90 95.0 kg

6HP21 78.0 kg

8HP70 87.0 kg

80 6HP19 77.0 kg 70

200

300

8HP45 77.0 kg 400

500

600

700

800

900 Torque [Nm]

ZF Automatic Transmissions – Weight Comparison

2

Clutch

Gearset 4

Brakes

Torque converter with torsional vibration damper

Gearsets 1 to 3

Mechatronics module

Vane-type oil pump (not visible) 3

Unbeatably flexible: our modular construction system

For the 8-speed automatic transmis-

The flexible modular construction system of the 8HP

sion, ZF set out to design and

is full of innovations and is well-suited to serve as

develop an entirely new gear set

the basis for a wide range of future development

concept. The result is a revolution

possibilities. The following technologies can be

in transmission design: a transmis-

implemented without altering the transmission

sion concept with 4 gearsets which

installation space:

requires only 5 shift elements – of which only two are open in any

• Hydrodynamically cooled clutch

given gear.

• Integrated starting clutch • Crankshaft starter generator • Integrated hybrid

The 8HP also requires no more than 3 multi-disk clutches and 2 brakes, which allows it to achieve a greater

As a future-proof transmission, the 8HP is also com-

degree of efficiency than other con-

patible with the following all-wheel-drive concepts:

cepts. As a result of the fact that only 2 shift elements are open per

• All-wheel drive center differential integrated

gear, drag losses in the transmission

• Integrated all-wheel drive system (IAS©)

are sustainably reduced. This effect

• Hang-on all-wheel-drive

is supported by the use of a new parallel-axis vane-type oil pump.

A B D E

1

2

3

4

5

6

7

8

C RS1 RS2

RS3

RS4

1 2 3 4 5 6 7 8 R A Gear

B Brake

C

D Clutch

4.70 3.13 2.10 1.67 1.29 1.00 0.84 0.67 -3.30

Spread 7.05

Ratio

Gear step

1.50 1.49 1.26 1.30 1.29 1.19 1.25

E

Transmission system 4

8HP

micro hybrid + HIS©

Base transmission with torque converter

mild hybrid Torque converter possible + electric motor

Modular hybrid construction system for 8HP HIS: Hydraulic Impuls Storage (HIS©) IAE: Integrated starting element IEP: Integrated electric pump

Recuperation Boosting

Stop/Start The engine is switched off during stand-still. When starting, the electric motor automatically starts the engine again.

The electric motor assists the engine when accelerating. The additional propulsive power enables the engine to be designed in a smaller, lighter, and more fuel-saving way (downsizing).

full hybrid with electric motor

Purely electric driving Electric starting (driveoff) Additional Features For the particularly fuel-intensive starting process, it is exclusively the electric motor which provides propulsion.

The vehicle also runs for a longer distance with the power supplied only by the electric motor. The required energy is provided by the battery.

8HP (for longitudinal installation) 300-1.000 Nm, for gasoline or diesel engines

Fuel Savings* 6% 5%

with start/stop (HIS©)

15%

as a mild hybrid

25%

as a full hybrid

Vehicle classes Standard and all-wheel drives

Compact vehicle class

Mid-size class/full-size vehicle class

Luxury vehicle class

SUVs/Pickups

*Compared with the 2nd-generation 6HP 6-speed automatic transmission in the NEDC

5

Sustainable concept for the powertrains of the future

The 8-speed automatic transmission

shuts off the engine when the vehicle comes to a

reduces overall fuel consumption by

stop and immediately re-activates the engine and

at least 6 % compared to present

transmission when the footbrake is released.

state of the art 2nd Generation ZF 6-speed automatic transmissions.

The flexibility of the 8HP makes it a future-proof

As an example, the CO2 emissions

partner for even more sustainable powertrain

of a six-cylinder engine with a

concepts such as hybrid solutions. In a full-hybrid

displacement of 2.5 liters can be

vehicle, the 8HP can help to reduce fuel consump-

reduced from 180 g/km to 169 g/km.

tion by an additional 25%. The modular structure

An important contribution to this

ensures significant long-term economic advantages

reduction is provided by the

over rigidly designed driveline configurations.

increasingly popular engine start/ stop function, which automatically

–5 % –3 % –6 % –5 % –15 % bis –25 %

Example: CO2 emissions of a sedan with a 2.5 liter, 6-cylinder engine 5-speed

180g/Km

169g/Km 161g/Km

144g/Km 127g/Km

6-speed 6-speed

8-speed 8-speed

8-speed 8-speed

1. Generation 2. Generation

Start-Stop (HIS©)

Mildhybrid

Fullhybrid

ZF Automatic Transmissions – Fuel Savings 6

Innovations that deliver for partners and drivers

With its transmission innovations,

ble or sporty – every wish for individualized driving

ZF seeks to achieve many goals: to

pleasure can be satisfied. Those who appreciate

satisfy reliable partnerships, create

agility will be happy to know that the most modern

sustainable solutions for the future,

adaptive shift strategies are used which enable

and – last but not least – excite

direct skip-shifts over multiple gears, even allowing

drivers worldwide. The 8HP shifts

for extreme downshifts such as 8th gear to 2nd gear.

faster and more precisely than a

In spite of the dry facts, maximum driving pleasure

professional driver, requiring less

is guaranted.

than 100 milliseconds to initiate a downshift when increased accelera-

The automotive world has expressed its enthusiasm

tion is desired. Whether comforta-

for the flexibility, variety of applications, and future potential of the 8-speed automatic transmission. The

Since 2006 ZF has consistantly won the readers‘ choice of the German magazine „auto motor und sport“ for the transmission category.

American trade magazine ‘Automotive News’ awarded ZF the 2010 PACE Award for the engineering of the 8HP.

7

ZF Friedrichshafen AG PO Box 650464 66143 Saarbrücken Germany Phone +49 681 920-0 Fax +49 681 920-2377 www.zf.com

Driveline and Chassis Technology