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Old 05-04-2007, 07:19 AM   #1
NYCshopper
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Default ZF Develops Automatic 8-Speed Transmission for Passenger Cars

ZF Develops Automatic 8-Speed Transmission for Passenger Cars



Press Release:
Quote:
Presentation to 1,000 engineers at the Vienna Motor Symposium

Consumption savings of six percent thanks to the new transmission concept with improved efficiency.

More power with same installation space.

Kit system for future hybrid and all-wheel drives

ZF has designed a new automatic transmission generation for passenger cars: With the automatic 8-speed transmission the chassis and driveline specialist succeeds once more in combining seemingly contradictory goals. The automatic ZF 8-speed transmission allows for additional fuel savings of approximately six percent compared with the already optimized automatic 6-speed transmission of the second generation. This is achieved above all by a completely new transmission concept. At the same time, the automatic 8-speed transmission transmits more power in comparison to the previous model, but still gets by with the same installation space and does not require more components. Last week, the new 8-speed transmission was presented for the first time at the 28th International Vienna Motor Symposium.

“Our main development target was to find a transmission concept which allows for significant additional fuel consumption reduction and thus offers tangible added value to our customers and drivers without making any compromises in terms of performance”, explains Dr. Michael Paul, ZF Executive Vice President, Technology and Group Executive of the Car Driveline Technology division. “The number of gears was not given top priority.”

Fuel consumption savings as development target
The new, more powerful ZF multi-ratio automatic transmission allows for consumption savings of six percent. This means that the excellent consumption values of the second-generation automatic ZF 6-speed transmission which entered volume production only in 2006 have been further improved considerably. To make it clear: Compared to an automatic 5-speed transmission which is still widely used today the consumption reduction amounts to approx. 14 %.

Two innovations are mainly responsible for these spectacular consumption values. Compared to the automatic 6-speed transmission, the basis of the new ZF automatic transmission generation is an entirely new transmission concept featuring four planetary gear sets and five shift elements. Only two shift elements are opened in each gear which leads to considerably lower drag losses. Besides the improved efficiency, this transmission concept features a higher total ratio. Modern torsional vibration damping systems in the torque converter also have a positive impact on consumption and CO2 emissions. These systems also allow for a quick lock-up of the converter clutch in the second generation automatic 6-speed transmission presented in 2006. Furthermore, ZF now uses a small vane cell pump mounted parallel to the axle.

Versatile combinations
Another development focus was the increase in performance. The power-to-weight ratio of the new automatic transmission is higher and can transmit a higher input torque at the same weight, in comparison to the previous model. The automatic 8-speed transmission gets by with the same installation space as the previous versions made by ZF. In terms of shift comfort, response and shifting speed, also the new automatic 8-speed transmission operates at the already very high level of the second generation of the automatic 6-speed transmission.

The equipment options offered with the new automatic 8-speed transmission for passenger car driveline technology are trend-setting. The new transmission has been designed in such a way that it can serve as a modular system for further starting and all-wheel concepts without changing the basic transmission concept. This way, a torque converter could be replaced by new clutches or could be omitted completely when an integrated starting clutch is used. The design engineers of the automatic 8-speed transmission have also paid attention to the compatibility with today’s and future ZF all-wheel concepts.

For the hybridization of the driveline, the automatic 8-speed transmission offers the possibility of implementing both a micro hybrid with a crankshaft starter generator and a full hybrid in the form of a parallel hybrid. All known hybrid functions can thus be implemented in combination with the new automatic 8-speed transmission
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Old 05-05-2007, 05:45 AM   #2
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The step ATs are getting more and more steps. Apparantly they want to get as close as possible to CVT...
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Old 05-07-2007, 05:47 PM   #3
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To make it clear: Compared to an automatic 5-speed transmission which is still widely used today the consumption reduction amounts to approx. 14 %.

So basically by swapping out a regular 5-speed auto with this 8-speed, you would basically get the fuel economy savings mandated by the new CAFE standards for the next 4 years without even having to change anything else in the car.
(the new CAFE standards are a 4% fuel efficiency increase each year after 2020 when the new minimum is going to be 35mpg)

Ya know, it sometimes is very tough to feel sorry for the automakers complaining that it can't be done, when this one single component can put them well on their way to meeting that new goal.
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Old 05-07-2007, 06:05 PM   #4
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Should be interesting how this all turns out especially for the automakers...on the side...can you imagine being down because you blew 8th gear?? hahaha
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Old 05-07-2007, 10:03 PM   #5
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Originally Posted by Hazdaz View Post
Ya know, it sometimes is very tough to feel sorry for the automakers complaining that it can't be done, when this one single component can put them well on their way to meeting that new goal.
At what cost? Can you imagine how much it will be to implement a transmission like that? Sure they could meet EPA regs ect but they won't be able to pay for it because consumers don't want to pay for it.
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Old 05-07-2007, 10:27 PM   #6
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Originally Posted by cdvma View Post
At what cost? Can you imagine how much it will be to implement a transmission like that? Sure they could meet EPA regs ect but they won't be able to pay for it because consumers don't want to pay for it.
The article doesn't state costs (unless I missed it), but it did specifically state that this new tranny is no larger than a 6-speed, and doesn't have any more parts. Usually more parts = higher complexity = higher price, so while I am sure that there is a decent mark-up on it over a regular 6-speed, I doubt it is astronomical. Mass-produce almost anything at high enough volumes, and you can get the prices way down.
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Old 05-08-2007, 08:44 AM   #7
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I want a 21 speed.

(More speeds = must be better, right?)

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Old 05-08-2007, 09:06 AM   #8
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Originally Posted by Hazdaz View Post
Ya know, it sometimes is very tough to feel sorry for the automakers complaining that it can't be done, when this one single component can put them well on their way to meeting that new goal.
I think mercedez is the only one producing a seven speed transmission, so it isn't like these thing are everywhere waiting to be put in to production.

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Old 05-08-2007, 09:15 AM   #9
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Originally Posted by SlideWRX View Post
I think mercedez is the only one producing a seven speed transmission, so it isn't like these thing are everywhere waiting to be put in to production.
the Lexus LS460 uses a Eight-speed sequential-shift automatic
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Old 05-08-2007, 03:09 PM   #10
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^ yep. why did you put in "sequential shift" though? It's just a regular automatic except you can use +/- function to select what gear you want!
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Old 05-08-2007, 04:25 PM   #11
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i dont understand the big deal about this transmission... granted i didnt read the article, but as NYCshopper already stated, the lexus LS460 already has an eight-speed autotransmission.
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Old 05-08-2007, 08:22 PM   #12
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i dont understand the big deal about this transmission...
Because now Lexus isn't the only company with an 8-speed. More competition, means better products at lower prices for everyone.
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Old 05-08-2007, 09:14 PM   #13
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Originally Posted by rice h8r View Post
^ yep. why did you put in "sequential shift" though? It's just a regular automatic except you can use +/- function to select what gear you want!
Copy & Paste from Lexus Web Site
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Old 05-08-2007, 10:17 PM   #14
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Old 05-09-2007, 12:23 PM   #15
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Originally Posted by SlideWRX View Post
I think mercedez is the only one producing a seven speed transmission, so it isn't like these thing are everywhere waiting to be put in to production.

IBthisonegoestoeleven

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Doesn't BMW have a 7 speed SMG for their M5 and M6?
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Old 07-05-2019, 06:03 AM   #16
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Default Generation 4 ZF 8HP70 Transmission..Lot Info.



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Quote:
Quote:
Future FCA Models To Get New 8-Speed Auto From ZF

Production will begin in 2022.

Upcoming rear-wheel drive and all-wheel drive vehicles from Fiat Chrysler Automobiles with front-longitudinal drive configuration will use a new eight-speed automatic gearbox from ZF. This is possible thanks to a new agreement between the two companies, for which ZF says is now the second-largest single order for the new eight-speed auto.

This is the fourth generation of the gearbox and it is developed especially with electrified vehicles in mind and uses an integrated electric drive. The transmission can be installed in cars from almost all segments as long as they have a front-longitudinal drive configuration. Production of the upgraded ‘box will begin in 2022 at ZF’s Saarbruecken plant. At a later date, it will be also assembled at further locations including the U.S. and China.

We are pleased being nominated as global transmission supplier by FCA. This is our second major order for the new 8HP and it confirms our strategy to focus on plug-in hybrids as an every-day solution and to develop attractive products in these areas,” ZF's CEO, Wolf-Henning Scheider, comments.

The new gearbox is an evolution of the current generation 8HP and can be used in cars with internal combustion engines and plug-in hybrids. It is believed FCA will use the automatic for its large U.S. models. The order is likely located somewhere in the low double-digit billion-dollar range.

The fourth generation of the eight-speed automatic will also be used by BMW. About three months ago, the Bavarian company and ZF signed an agreement which marks the largest single order in ZF’s history. According to unofficial information, the order is worth between $17 and $20 billion. A spokesman for ZF confirmed FCA’s deal “is very large, and not much smaller than BMW.”

Source: ZF
Why ZF's Eight-Speed Is the Best Automatic Transmission

Its capabilities are so broad that it's displacing dual-clutch units, too. Two words: shift quality. The 8HP transmission from German supplier ZF is quick enough to serve sports cars and graceful enough for large luxury sedans, and it combines those elements of speed and smoothness whether it’s installed in an Aston Martin, a Rolls-Royce, or a Jeep.

Albert Dick, vice president of car powertrain technology at ZF, says the 8HP’s deeply satisfying shifts are rooted in factors ranging from the quality of the solenoids to the manufacturing methods to the control software. They’re also a product of a fundamental design that determines how the four planetary gearsets, three clutches, and two brakes in every 8HP gearbox are parsed into eight forward ratios. All one-gear and two-gear shifts use just two shifting elements: one opens, another closes. The 8HP also executes certain multigear shifts in this manner; witness the leaps from sixth gear to third and even eighth to second.

The 8HP transmission comes only in longitudinal form for rear- or all-wheel-drive vehicles, and we prefer it immensely to ZF's transverse alternative, a nine-speed. In 2017, some 3.5 million 8HP transmissions were built for a laundry list of manufacturers that includes Aston Martin, BMW, Fiat Chrysler, Jaguar Land Rover, and the Volkswagen Group. Beyond performance, the eight-speed’s appeal is rooted in its versatile modular design. It can accommodate a maximum torque output from as low as 162 pound-feet up to 770. It is compatible with a variety of all- and four-wheel-drive systems, such as an integrated center differential or a two-speed transfer case. The ability to swap the torque converter for an electric motor, as BMW has done, allows automakers to develop hybrid variants with minimal changes to the drivetrain. And the commonalities among all 8HP gearboxes allow companies to share core elements between vehicles as different as the Dodge Demon and the Ram 1500, minimizing development costs. “We keep the same power flow through all of those applications, so we can carry over the calibrations, the software, all of those tools that keep that transmission shifting smoothly,” says Eric Burnett, chief engineer for eight-speed, rear-wheel-drive transmissions at Fiat Chrysler.

Has the dual-clutch transmission met its match, then? You might think that’s the case, given the recent defections by the Audi RS5 and the BMW M5, which switched from dual-clutch transmissions to ZF’s 8HP torque-converter automatics. That’s also the opinion of Andy Palmer, CEO of Aston Martin, who claims ZF’s 8HP is lighter, cheaper, and quicker than a dual-clutch transmission. “Ten years ago, [the dual-clutch] still looked like the transmission of the future. Now it is starting to look like the transmission of the past,” he tells us. But the DCT finds refuge in supercars. The added length of a torque converter can be prohibitive in a mid-engine architecture, and precise launch-control programs provide an advantage in acceleration. And engineers maintain that a good dual-clutch ’box does shift quicker. “For our kind of product, it’s about a really fast shift, which the pre-engagement element of a dual-clutch gearbox helps us with. We think that’s still got a decent speed advantage,” says Marcus Waite, chief engineer of the McLaren Senna.

But for just about every other vehicle, though, it's hard to argue that anything can do the job better than the ZF eight-speed.
Why So Many Carmakers Use ZF's Eight-Speed Automatic
It's on-par with dual-clutch in terms of performance, but smoother, cheaper, and easier to package. It's no wonder so many cars use it.

The Aston Martin DBS Superleggera. The Toyota Supra. The Alfa Romeo Giulia Quadrifoglio. The BMW M5. The Jeep Grand Cherokee Trackhawk. The Rolls-Royce Phantom. Though these cars are all different, there's one thing they (and many other cars) have in common: ZF's 8HP eight-speed torque converter automatic transmission.

First introduced in 2008, ZF's eight-speed gearbox has come to occupy the transmission tunnels of countless new cars, from big American trucks to compact hatchbacks and ultra-luxurious grand tourers. In some cases, it's even replaced dual-clutch transmissions. ZF sold an astonishing 3.5 million units in 2017 alone, according to our colleagues at Car and Driver. How has the 8HP come to conquer the market? Well, it's very good at a lot of things.

As Jason Fenske of Engineering Explained says in his latest video above, the ZF eight-speed has been engineered to fulfill many different roles in a single, compact package. It can be quiet and well-behaved in a Ram 1500, or wildly responsive on track while bolted into a new M5. It can be used as a transaxle, like it is with every new Aston Martin, or sit right behind the engine, like in the Giulia. It's also not any bigger than the company's last-gen transmissions, despite having more forward gears. That means companies like Dodge don't have to design an entirely new chassis with a bigger tunnel to fit a new, bigger gearbox. It's also lighter than your average dual-clutch, broadening the performance appeal. It truly checks all the boxes.
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Old 07-05-2019, 06:11 AM   #17
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^^^^^^
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ZF launches product offensive for hybrid and electric drive systems, automated driving, integrated safety, and chassis


ZF is launching a product offensive for hybrid and electric vehicles, active chassis systems, integrated safety, and automated driving. The Group will showcase its next-generation mobility solutions at the forthcoming IAA.

ZF is pursuing two directions in electromobility. It is laying the foundation for a new breed of battery-electric vehicles with its new 8-speed automatic transmission for hybridization.

The modular construction system enables mild, full, and plug-in hybrid drives to achieve top performances between 24 and 160 kW. The power electronics are no longer designed as a separate unit, but instead are fully integrated into the transmission housing without increasing the outer dimensions of the transmission. With a new, significantly smaller hydraulic control unit, ZF has created the required installation space for the electric and electronic components.

8-speed transmission

PHEVS. ZF estimates that at least 70% of all new vehicles in 2030 will still have an internal combustion engine. Nevertheless, a plug-in hybrid drive could considerably lower the engine’s CO2 emissions. This is contingent on electric range and electric power, both of which must allow for driving in everyday traffic with battery power only.

ZF has laid the foundation for this with the plug-in model of the new generation 8-speed automatic transmission. The electric motor has a maximum power of 160 kW and a continuous output of 80 kW. The maximum torque, which can be attained without actuating the internal combustion engine, is 450 N·m, thus allowing for swift passing, even in e-mode.

This does not require a significant increase of the packaging size since ZF relies on a new generation of internally developed electric motors and uses welded copper rods instead of coiled copper wire. This technology, known as the “hairpin technique,“ allows the copper fill level to be significantly increased, which has a decisive impact on the power density.

Mild hybrids. In addition to plug-in hybrids with high voltages of around 300 volts, mild hybrids will also play a big role in the coming decade. These have a voltage level of 48 volts and allow for considerable CO2 savings by generating power through regenerative braking recovery that can later be used as drive power.

Furthermore, mild hybrids lower pollutant emissions by providing additional power during launch and acceleration processes—driving conditions in which conventional internal combustion engines emit a relatively high amount of pollutants in a short amount of time.

Forty-eight-volt drives can be installed on several locations in the driveline. Installation on the crankshaft at the engine output (“Position 1”) and on the input shaft (“Position 2”) are particularly efficient. The new generation from ZF is suitable for both installation types. The electric motor can reach a maximum power of up to 25 kw and thus optimally support the internal combustion engine in virtually all operating parameters.

Power Electronics. Electric motors must be controlled via power electronics, which both convert the direct current from the battery into the required alternating current and control the power and speed of the electric motor. These power electronics are often housed in a separate, shoebox-sized box for all series hybrid transmissions. However, with the fourth generation, ZF has integrated the complete power electronics into the transmission housing for the first time.

This is a great advantage to automotive manufacturers since hybrid drive assembly would no longer be considerably more complex than that of a conventional transmission. In addition, fewer high-voltage cables are needed in the vehicle, which enhances safety.

The engineers at ZF were faced with the challenge of fully integrating the power electronics into the transmission without increasing the outer dimensions. They achieved this through an ingenious cooling concept, as well as through several other developments.

The power semiconductors, especially the IGBTs for the high-volt model, produce a relatively high amount of waste heat. This is dissipated by connecting the power electronics to the refrigerant circuit of the vehicle‘s air conditioning system. However, the most important development was the considerable decrease in the size of the hydraulic control unit, which triggers mechanical shifts in the transmission.

The hydraulic control unit in the current generation of the 8-speed automatic transmission requires a volume of 3.1 liters, but in the next generation, it will shrink to 1.8 liters. This is made possible primarily by using direct shifting valves. In contrast to the electric pressure actuators that were previously used, these electromagnetic actuators no longer require additional pistons and bushings.

Intelligent adaptation. Each additional component of the new 8-speed construction kit was also intelligently designed for hybrid operation. This is clearly evident when it comes to the oil circuit.

Previously, two oil pumps were used: a very efficient vane cell pump driven directly by the internal combustion engine and a second electric pump and/or pulse memory for electric operation. In the future, a single power-split pump will be used.

When the internal combustion engine is shut down, it is driven by a small, directly attached electric motor. The mechanics of the new transmission system also contribute to efficient hybrid operation.

Although the body remains the same with four planetary gear sets and five shift elements, efficiency was further increased by fine-tuning the friction power. Due to this, CO2 emissions were lowered by one gram per kilometer during operation with the internal combustion engine. During electric operation, the range has increased accordingly.

Comfort. he new generation 8-speed automatic transmission is designed for lengthwise installation of the engine and transmission—a drive configuration that will be successful especially in the premium segment because it satisfies the high demand for comfortable operation and noise reduction.

Achieving this during hybrid operation is partly due to the solid mechanical foundation. Eight gears allow for transmission stepping of up to 8.6 with low gear steps, and thus low speed steps, over a wide speed range. In addition, the ZF-developed, centrifugal pendulum vibration absorber was optimized such that the driver barely feels the switch from electrical operation to operation with the internal combustion engine.

In the future, the transmission control module will no longer be based on characteristic maps, but rather on mathematical models of all system components. This is an important prerequisite for satisfying the growing complexity of future drivelines.

ZF will begin manufacturing the new generation 8-speed automatic transmission in Saarbrücken, Germany, in 2022. The market launch in China and the United States will follow shortly thereafter.

Two-speed electric drive

In parallel with its hybrid drive, ZF is working on improving purely electric drivelines. An important step is the world premiere of its electric two-speed drive system for passenger cars. This compact concept brings together an electric motor producing a maximum output of 140 kW (190 hp), a two-stage switching element, and power electronics. This can increase the range of each battery charge by up to 5% compared with a single-stage drive system.

Automated driving

The ‘Flying Carpet 2.0’ predictive chassis uses comprehensive sensors and smart algorithms to control suspension, braking, and steering systems. This largely decouples the vehicle superstructure from road unevenness and the dynamic effects of driving. As well as more comfort, it means better handling and safety. Comfort is key, especially in the development of fully automatic and autonomous driving, because it means that time spent in a vehicle can be used for activities such as reading and relaxing.

ZF’s complete systems include sensors and the ZF ProAI central computer in a range of performance levels. This makes ZF solutions scalable, flexible, and adaptable to a variety of market segments. That in turn allows car manufacturers to comply with the basic requirements of Euro NCAP 2022. And as ZF coPilot, it allows automated driving functions at SAE Level 2+.

ZF ProAI RoboThink is a high-performance version for people movers and cargo movers that enables Levels 4 and 5 autonomous driving. By acquiring WABCO, ZF aims to be able to provide complete automated driving systems for commercial vehicles as well.
ZF 8HP70 Transmission Problems & Specs
The purpose of adding additional gears to a transmission is to allow the engine to operate at lower RPMs when at speed (like on the highway). This not only saves fuel, but also enables a higher top speed in certain applications. The ZF 8 speed transmission known as the 8HP70 transmission, is able to achieve the performance parameters of cars like the Maserati Quattroporte and Jeep grand Cherokee SRT8, while still providing smoothness required for a Rolls Royce Phantom and Aston Martin Rapede. But the ZF 8HP70 transmission can also be found in cars like the Dodge Charger and the F30 BMW 3-Series. Plus, the Chrysler Corporation / FCA even produces them under license in the United States (Chrysler TorqueFlight 8). With the exception of this licensing deal, the ZF 8HP70 transmission was sold as a kit to automakers, who would then apply in their own 8HP70 controller software, torque converter and other components to suit their application. Although this 8-speed automatic transmission is found in a number of different cars and trucks, the way that it performs will vary greatly because of these alterations.

8HP70 Transmission Overview

The ZF 8HP70 transmission uses four planetary gearsets and five multi-plate clutch packs (3 rotating and 2 brake). When the transmission is in operation, only two clutches are open. This significantly reduces spin loss and increases fuel efficiency. The second generation of the 8HP70 transmission (2014 MY) reduces this spin loss even further by integrating springs into the clutch packs so that the friction elements stay completely open.

The ZF 8HP70 torque converter is able to achieve lockup in all 8 gears for maximum performance and efficiency. The 8HP70 transmission can also downshift from 8th directly to 2nd when conditions warrant. If equipped, Manual Shift Mode can execute driver requested gear changes in just 200 milliseconds. This ZF 8-speed automatic may also have shift-by-wire functionality which eliminates the physical connection between the shifter and the transmission.

Optimal pressure control in the ZF8HP70 transmission is achieved by using a chain driven offset variable displacement pump. This also allows for the 8HP70 hydraulic impulse oil storage system, or 8HP70 HIS system for short. If the vehicle application is equipped with a start/stop system, the ZF 8HP70 start/stop system will be able to engage the appropriate clutch pack when the driver lets off of the brake pedal, using stored hydraulic pressure. The reaction time varies from 1.5 seconds to 350 ms, depending on the generation.

ZF 8HP70 Transmission Recalls

– Recall ID – NHTSA: 16V24000 – ZF 8 Speed Automatic Transmission

— Summary
In April 2016, Fiat Chrysler / FCA recalled 811,290 Chrysler Group vehicles equipped with the ZF 8-speed transmission and monostable gear selector. These vehicles include:
2014-2015 Jeep Grand Cherokee
2012-2014 Chrysler 300
2012-2014 Dodge Charger

— Consequence
Due to the nature of the shifters design, it always returns to the center position, which may confuse some drivers. According to the recall, there may not be adequate warning to the driver when they open their door and the transmission is not in the Park position. In such a scenario, the vehicle may still be in gear or placed in Neutral. If this should happen, the vehicle could roll away unexpectedly, causing serious injury or damage. The death of Star Trek actor Anton Yelchin is speculated to have been caused by this shifter’s design.

— Remedy
Dealers were instructed to update the vehicle software to alter the shifter’s behavior. For more information, owners may contact Chrysler customer service at 1-800-853-1403 (refer to the Chrysler recall S27) or the National Highway Traffic Safety Administration at 1-888-327-4236

Recall 14V-161 / P13 – Failed Park engagement

2014 Ram 1500 5.7L Hemi and 8-speed automatic transmission

– Summary
According to the recall, some 125 copies of the 2014 Ram 1500 equipped to with the 8HP transmission may have had improperly machined Park rod guide plate mounting surfaces inside of the transmission case, which could cause the fasteners to loosen, preventing the Park prawl from fully engaging.

– Consequence
If the above condition occurs, the transmission may slip out of the park position and unexpectedly roll away, causing serious injury or property damage.

– Remedy
The transmission will have to be replaced. Concerned owners can contact Chrysler customer service at 1-800-853-1403. You can also contact the National Highway Traffic Safety Administration at 1-888-327-4236

8HP70 Transmission Specs

General – 8-speed automatic
Application – RWD/AWD/4WD
Max Engine Torque – 516 lb-ft
Variations – with/without engine stop/start HIS system and 4WD/AWD
Production Began – 2008
Weight – 207 lbs +/-
Fluid Type – ZF Lifeguard 8

8HP70 Transmission Gear Ratios

**actual gear ratios may vary depending on application
***Gen 1 (gear ratio spread 7.0:1) / Gen 2 (gear ratio spread 7.8:1)
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Old 07-08-2019, 11:24 AM   #18
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Interesting. This new one should align with the timeline Jeep said to expect an electric Wrangler.
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Old 07-09-2019, 06:58 AM   #19
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Default Jeep Recalls 2014 Cherokee Again as ZF Nine-Speed Transmission Problems Continue

Serious issues, including transmissions that can suddenly drop into neutral, have persisted.


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Jeep Recalls 2014 Cherokee Again as ZF Nine-Speed Transmission Problems Continue

Since Fiat Chrysler introduced the ZF nine-speed automatic transmission to the 2014 Jeep Cherokee, owners have continued to report multiple quality and safety problems stemming from this transmission.
This latest recall affects 2014 Jeep Cherokee V-6 models for a clutch that can become stuck and cause the transmission to drop into neutral.
FCA has issued 11 software updates intending to fix rough shifts, stuck gears, and more.

Transmission problems continue to pester Jeep Cherokee owners with rough shifts, random drops into neutral, stalling, and other safety concerns in the six years since this crossover debuted, according to complaints logged by the National Highway Traffic Safety Administration (NHTSA).

Fiat Chrysler is again recalling the 2014 Cherokee, its first model year on the KL platform, for defects with the ZF nine-speed automatic transmission after a 2016 recall that affected 329,540 cars—including four other models that used this transmission—for unexpectedly shifting into neutral. The new recall affects only 2014 Cherokee models with 3.2-liter V-6 engines. On these vehicles, FCA said a valve can stick and prevent a clutch from disengaging, which would then prompt the transmission to shift into neutral. More than 81,000 Cherokees are included. At least three out of every 100 cars in this population have undergone warranty work for the problem, FCA said. According to what NHTSA has posted separately, Jeep dealers will apply a software update starting in August.

But since the Cherokee went on sale in late 2013—after FCA delayed its launch by weeks to fix transmission calibration problems—the automaker has supplied Jeep dealers with no fewer than 11 separate software updates through 2016 intended to fix a multitude of transmission problems, all without formal recalls and only if customers reported the problems to their dealers. Those updates attempted to fix delayed downshifting, stuck gears, poor throttle response, surging, "busy" shift behavior, and rough coasting—the majority of which can be found reported in the more than 1500 powertrain complaints submitted by 2014 Jeep Cherokee owners to NHTSA as of June 25.

Software update after software update continued until February 2015, when FCA advised dealers to replace one of the clutches just weeks after it released a software update intended to stop a clutch ring from "dislodging," according to filings on the NHTSA database. In this same month, while Jeep dealers were reportedly replacing more than a dozen transmissions a week, FCA recalled nearly 78,000 Chrysler 200 sedans for unrelated electrical problems that caused the same nine-speed automatic to shift into neutral. By March 2016, the problem became so widespread that FCA told dealers they could begin ordering replacement transmissions without receiving prior factory approval for repairs. In May 2016, FCA recalled the Chrysler 200 again for faulty parking pawls and rods that could cause the transmission to be in neutral when owners thought it was in park.

Owners of Jeep Renegade, Ram ProMaster City, Fiat 500X, Land Rover Discovery Sport, Range Rover Evoque, Acura TLX, and Honda Pilot models with this same transmission have reported similar issues, with varying severity, over the same time period. When ZF issued a recall in August 2016 that included a majority of FCA cars—this was the original recall that affected 2014 and 2015 Cherokee models—the company blamed a bad crimp on a wiring harness that was causing these transmissions to shift into neutral. Despite ZF making a production line change to address this specific problem in July 2014, FCA continued releasing updates that did not appear to fix shift-quality problems. It even instructed dealers to train "Qualified Subjective Shift Quality Auditors" whose job is to drive customer vehicles and follow a lengthy procedure to calibrate the transmission's adaptive learning software.

Newer models including the Honda Passport and Jaguar E-Pace also use this same transmission.
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