ATTESA
Encyclopedia
ATTESA is a four-wheel drive
Four-wheel drive
Four-wheel drive, 4WD, or 4×4 is a four-wheeled vehicle with a drivetrain that allows all four wheels to receive torque from the engine simultaneously...

 system used in some automobiles produced by the Japanese automaker Nissan, including some models under its luxury marque Infiniti
Infiniti
is the luxury division of automaker Nissan. Infiniti officially started selling vehicles on November 8, 1989 in North America. Marketing operations have since grown to include the Middle East, South Korea, Russia, Taiwan, China, Ukraine and the United Kingdom. Infiniti began sales in additional...

.

ATTESA

The 'mechanical' ATTESA system was developed for transverse layout vehicles and introduced with the RNU12 Bluebird in the Japanese market, entering production in September 1987. The system ran right throughout the U12 series (RNU12/HNU12) and was fitted to numerous U12 models with differing engine and gearbox combinations. An almost identical system is fitted to the RNN14 GTi-R Pulsar and the HNU13 Bluebird and the HNP10 Primera, finding usage in numerous other nissan models.

Quite similar to offerings from other manufacturers, drive passes from the gearbox to a centre viscous limited slip differential
Limited slip differential
A limited slip differential is a type of differential gear arrangement that allows for some difference in angular velocity of the output shafts, but imposes a mechanical bound on the disparity...

, into a transfer case splitting drive to a co-located front differential, and tail shaft connected to the vehicles rear differential.

2000+ ATTESA Update

In the new system, as with a normal FWD car, the gearbox contains a differential that drives the front wheels. However, an extra shaft from this differential also drives a bevel gear housed in the transfer case that permanently turns the driveshaft (i.e. there is no longer a "centre" differential). Housed in the rear differential is a viscous coupling that in normal conditions is disengaged. This means that for general driving, the system is FWD only.
When the computer detects slippage of the front wheels, the viscous coupling engages and transfers up to 50% of the torque to the rear wheels. This system is superior in some aspects as there is less loss due to the normal FWD operation, however it is no longer a full-time 4wd system.

ATTESA-ETS

The Electronic Torque Split version of this all-wheel drive architecture is a more advanced ATTESA system developed for Nissan vehicles with a longitudinal drive train layout. It was first used in August 1989 in the R32 Nissan Skyline GT-R and Nissan Skyline GTS4. Although the Skyline GT-R is exclusively AWD and manual, ATTESA-ETS is also used in Nissan models that are also available as RWD and also with automatic transmissions fitted, such as the A31 Nissan Cefiro which was the second Nissan to feature the system exactly a year later in August 1990, and vehicles based on the Nissan FM platform
Nissan FM platform
The Nissan FM platform is a modern FR automobile layout. The name is derived from the "front midships" location of the engine, referring to the engine's center of mass being located behind the front axle centerline, shifting weight to the middle of the car, leaving the front suspension less...

 (which are sold in certain markets under the Infiniti
Infiniti
is the luxury division of automaker Nissan. Infiniti officially started selling vehicles on November 8, 1989 in North America. Marketing operations have since grown to include the Middle East, South Korea, Russia, Taiwan, China, Ukraine and the United Kingdom. Infiniti began sales in additional...

 luxury brand).

The ATTESA-ETS version uses a mostly conventional RWD gearbox. Drive to the rear wheels is constant via a tailshaft and rear differential
Differential (mechanics)
A differential is a device, usually, but not necessarily, employing gears, capable of transmitting torque and rotation through three shafts, almost always used in one of two ways: in one way, it receives one input and provides two outputs—this is found in most automobiles—and in the other way, it...

, but drive to the front wheels is more complex by utilizing a transfer case
Transfer case
A transfer case is a part of a four-wheel-drive system found in four-wheel-drive and all-wheel-drive vehicles. The transfer case is connected to the transmission and also to the front and rear axles by means of drive shafts...

 on the rear of the gearbox.

The drive for the front wheels comes from a transfer case bolted on the end of an almost traditional Nissan RWD transmission although the tail-shaft is different to couple to the transfer case. A short driveshaft for the front wheels exits the transfer case on the right side. Inside the transfer case a multi-row chain drives a multi-plate wet clutch pack. Drive from the chain is apportioned using this clutch
Clutch
A clutch is a mechanical device which provides for the transmission of power from one component to another...

 pack in the transfer case "differential"
Differential (mechanics)
A differential is a device, usually, but not necessarily, employing gears, capable of transmitting torque and rotation through three shafts, almost always used in one of two ways: in one way, it receives one input and provides two outputs—this is found in most automobiles—and in the other way, it...

 (the system thus does not involve a regular gear differential as in a full-time 4WD layout, but rather a center clutch), similar to the type employed in the Steyr-Daimler-Puch system in the Porsche 959
Porsche 959
The Porsche 959 is a sports car manufactured by Porsche from 1986 to 1989, first as a Group B rally car and later as a legal production car designed to satisfy FIA homologation regulations requiring that a minimum number of 200 street legal units be built....

. This unit is lubricated with its own dedicated NS-ATF oil supply (Nissan Special ATF) and is not in any way connected to the oil in the transmission. Some Nissan models have an external oil cooler with an electric oil pump to cool this oil.

Situated the rear differential(?) is a high pressure, low volume electric oil pump. This pump pressurizes Normal ATF oil (0-288psi) into the transfer case to engage the clutchpack. This oil only engages the clutchpack and does not mix with the NS-ATF lubricating the tranfercase. The higher the oil pressure the transfer case is supplied with from the pump, the more the clutch pack engages, enabling the torque to the front wheels to be varied. Exiting the transfer case, the front drive shaft runs along the right side of the transmission, into a differential located on the right of the engines sump. This is a cast aluminum unit, with the sump and front diff made as one joined unit that can not be separated. The front right axle is shorter than the left, as the differential is closer to the right wheel. The front left axle runs through the engine's sump to the left wheel. Video of ATTESA system components

To control the ATTESA-ETS system, there is a 16-bit microprocessor
Microprocessor
A microprocessor incorporates the functions of a computer's central processing unit on a single integrated circuit, or at most a few integrated circuits. It is a multipurpose, programmable device that accepts digital data as input, processes it according to instructions stored in its memory, and...

 that monitors the cars movements at 10 times per second to sense traction loss by measuring the speed of each wheel via the ABS sensors. Also a three axis G-Sensor mounted underneath the center console feeds lateral and longitudinal inputs into an ECU
ECU
ECU may refer to:Automotive terms* Electronic control unit, a generic term for any embedded system that controls one or more of the electrical systems or subsystems in a motor vehicle...

, which controls both the ATTESA-ETS 4WD system and the ABS system. The ECU can then direct up to and including 50% of the power to the front wheels. When slip is detected on one of the rear wheels (a rear wheel turn 5% or more than the front wheels), the system directs torque to the front wheels which run a non LSD diff. Rather than locking the AWD in all the time or having a system that is "all or nothing", the ATTESA-ETS system can apportion different ratios of torque
Torque
Torque, moment or moment of force , is the tendency of a force to rotate an object about an axis, fulcrum, or pivot. Just as a force is a push or a pull, a torque can be thought of as a twist....

 to the front wheels as it sees fit. This provides the driver with an AWD vehicle that performs like a rear wheel drive vehicle in perfect conditions and can recover control when conditions aren't as perfect.

From factory, the system is set up to provide slight oversteer in handling, and in fact the harder the car is cornered, the LESS the 4wd system engages the front wheels. This promotes the oversteer rather than understeer which is apparent in most AWD/4WD vehicles. The advantage to a more traditional ATTESA (Viscous LSD
Viscous coupling unit
A viscous coupling is a mechanical device which transfers torque and rotation by the medium of a viscous fluid. It is made of a number of circular plates with tabs or perforations, fitted very close to each other in a sealed drum. Alternate plates are connected to a driving shaft at one end of the...

) system is response in hundredths of a second.

Some models fitted with the ATTESA-ETS system, such as the Nissan RS4 Stagea, have a "S" button on the dash. This will bypass the control system of the ATESSA-ETS ecu and lock the transfer case into full 4wd. This is to be uses at low speeds in snowy and icy conditions only as understeer is greatly increased in this mode.

A reviewer said that the 2009 Infiniti G37's ATTESA-ETS had more sportiness and faster reaction time than competing AWD systems such as Audi
Audi
Audi AG is a German automobile manufacturer, from supermini to crossover SUVs in various body styles and price ranges that are marketed under the Audi brand , positioned as the premium brand within the Volkswagen Group....

's quattro
Quattro
quattro is the name used by Audi AG to indicate that four-wheel drive technologies or systems are used on specific models of the Audi automobiles....

, BMW
BMW
Bayerische Motoren Werke AG is a German automobile, motorcycle and engine manufacturing company founded in 1916. It also owns and produces the Mini marque, and is the parent company of Rolls-Royce Motor Cars. BMW produces motorcycles under BMW Motorrad and Husqvarna brands...

's xDrive
Xdrive
The term Xdrive may refer to:* BMW xDrive, an all-wheel-drive system that powers the BMW X3 and the BMW X5, and also available in certain 3 Series and 5 Series models....

, and Mercedes-Benz
Mercedes-Benz
Mercedes-Benz is a German manufacturer of automobiles, buses, coaches, and trucks. Mercedes-Benz is a division of its parent company, Daimler AG...

's 4MATIC
4MATIC
4Matic is the name of an AWD four-wheel drive system developed and used by Mercedes-Benz. It is designed to increase traction in slippery conditions....

.

ATTESA-ETS Pro

In 1995, with the introduction of the R33 Skyline GT-R, Nissan introduced a new version of their ATTESA system. It was named ATTESA-ETS Pro, as an upgrade from the earlier ATTESA ETS. It was standard equipment in the R33 Skyline GT-R Vspec model, however it was offered as an option on the standard R33 Skyline GT-R, and called the "Active LSD option". It was also standard equipment on all R34 Skyline GT-R models.

ATTESA-E-TS Pro differs from the standard ATTESA-E-TS in a few ways. Where ATTESA-E-TS controls the front to rear torque-split, the Pro is also capable of left-and-right torque split to the rear wheels. This is done via an active rear limited-slip differential. Additionally, the ATTESA-E-TS Pro was marketed as controlling the four-wheel independent ABS braking system. This is not part of the AWD system, but the ECU makes use of the same sensors to determine wheel slip and traction.

On ATTESA-E-TS Pro equipped vehicles, the front differential remains a standard differential, not being linked to the ATTESA-E-TS Pro system.

R33 updated wheel speed sensors 100 times a second
R34 updated wheel speed sensors 1000 times a second.

ATTESA-ETS (GT-R version)

The 2009 Nissan GT-R
Nissan GT-R
The Nissan GT-R is a sports car produced by Nissan released in Japan on December 6, 2007, the United States on July 4, 2008, and the rest of the world in March 2009.-History:...

 uses an updated version of the ATTESA-E-TS, and is designed to work with the car's rear transaxle layout. The system is unique in a way that it utilizes two driveshafts under the vehicle's centerline, with a second driveshaft running slightly to the right of the main driveshaft and engine sending power to the front wheels. It is so far, the only rear transaxle-based AWD system for a front engined car in production.

Unlike the previous ATTESA systems which relied heavily on mechanical feedback, the system in the GT-R uses electronic sensors and hydraulically-actuated clutches. It also has a yaw-rate feedback control system, effectively managing slip angle. Front rear torque split can go from 2:98 during a standing start to a maximum of 50:50

Models and ATTESA type

Nissan Model Year Released ATTESA type
Avenir
Nissan Avenir
The Nissan Avenir is a line of station wagons beginning production in May 1990 by Nissan of Japan, with the budget minded delivery van starting out as the Avenir Cargo, then being renamed in 1999 as the ' aimed primarily at the commercial market. It replaced the long-serving Nissan Bluebird...

1990 ATTESA
Avenir
Nissan Avenir
The Nissan Avenir is a line of station wagons beginning production in May 1990 by Nissan of Japan, with the budget minded delivery van starting out as the Avenir Cargo, then being renamed in 1999 as the ' aimed primarily at the commercial market. It replaced the long-serving Nissan Bluebird...

1998 ATTESA
Bluebird
Nissan Bluebird
Although Nissan's own materials indicate that the Bluebird name emerged in 1959, some records show that the name first adorned a 988 cc, four-door sedan in 1957, which was part of the company's 210 series...

1989 ATTESA
Primera
Nissan Primera
The Nissan Primera is a medium sized family car produced by the Japanese automaker Nissan for the Japanese domestic and European markets.-Nissan Primera P10 :...

1991-1999 ATTESA
Prairie
Nissan Prairie
The second generation of the Prairie was introduced September 1988, and it was renamed the Nissan Axxess when sold in North America. The vehicle sold for six years in Canada, and in 1990 only in the United States....

1989 ATTESA
Prairie
Nissan Prairie
The second generation of the Prairie was introduced September 1988, and it was renamed the Nissan Axxess when sold in North America. The vehicle sold for six years in Canada, and in 1990 only in the United States....

1992 ATTESA
Prairie
Nissan Prairie
The second generation of the Prairie was introduced September 1988, and it was renamed the Nissan Axxess when sold in North America. The vehicle sold for six years in Canada, and in 1990 only in the United States....

1994 ATTESA
Pulsar
Nissan Pulsar
The Nissan Pulsar is an automobile that was produced by the Japanese automaker Nissan from 1978, when it debuted as a subcompact car, to 2007, when it was replaced in all markets by the Nissan Tiida. It was originally conceived as a replacement for Nissan's first front-wheel drive platform, the...

1989 ATTESA
Pulsar
Nissan Pulsar
The Nissan Pulsar is an automobile that was produced by the Japanese automaker Nissan from 1978, when it debuted as a subcompact car, to 2007, when it was replaced in all markets by the Nissan Tiida. It was originally conceived as a replacement for Nissan's first front-wheel drive platform, the...

1997 ATTESA
Pulsar
Nissan Pulsar
The Nissan Pulsar is an automobile that was produced by the Japanese automaker Nissan from 1978, when it debuted as a subcompact car, to 2007, when it was replaced in all markets by the Nissan Tiida. It was originally conceived as a replacement for Nissan's first front-wheel drive platform, the...

1999 ATTESA
Sunny
Nissan Sunny
The Nissan Sunny is a small car from Nissan. It was launched in 1966 as the Datsun 1000 and although production in Japan ended in 2004, it remains in production today for the African, American and Sri Lankan markets. In the US, the later models were known as the Nissan Sentra; in Mexico, the Sunny...

1989 ATTESA
Sunny
Nissan Sunny
The Nissan Sunny is a small car from Nissan. It was launched in 1966 as the Datsun 1000 and although production in Japan ended in 2004, it remains in production today for the African, American and Sri Lankan markets. In the US, the later models were known as the Nissan Sentra; in Mexico, the Sunny...

1992 ATTESA
Sunny
Nissan Sunny
The Nissan Sunny is a small car from Nissan. It was launched in 1966 as the Datsun 1000 and although production in Japan ended in 2004, it remains in production today for the African, American and Sri Lankan markets. In the US, the later models were known as the Nissan Sentra; in Mexico, the Sunny...

1997 ATTESA
Sunny
Nissan Sunny
The Nissan Sunny is a small car from Nissan. It was launched in 1966 as the Datsun 1000 and although production in Japan ended in 2004, it remains in production today for the African, American and Sri Lankan markets. In the US, the later models were known as the Nissan Sentra; in Mexico, the Sunny...

2000 ATTESA

|[Infiniti QX4]
| 1997-2003
ATTESA E-TS system is used in the following models:
  • R32 and R33 (1989-1997) GTS4 Skyline
    Nissan Skyline
    The first Skyline was introduced in April 1957, by the Prince Motor Company, and was marketed as a luxury car. It featured a 1.5 L GA-30 engine producing 44 kW @ 4400 rpm. It used a de Dion tube rear suspension and was capable of 140 km/h . The car weighed around 1300 kg...

  • GT-R
    Nissan Skyline GT-R
    The Nissan Skyline GT-R is a Japanese sports car based on the Nissan Skyline range.The first GT-Rs were produced from 1969–1973. After a 16 year hiatus since the KPGC110 in 1972, the GT-R name was revived in 1989 with the Skyline R32. This car was nicknamed "Godzilla" by the Australian motoring...

     - 1989–2003
  • Nissan Stagea
    Nissan Stagea
    The Nissan Stagea commonly referred to as the Skyline wagon when the 2.5 turbo is fitted, is a station wagon originally produced by Nissan in 1996 as direct competition for the Subaru Legacy Touring wagon in the Japanese Domestic Market.There are 3 different versions of the Stagea, WC34 Series 1 ,...

  • A31 Cefiro
    Nissan Cefiro
    The Nissan Cefiro is a intermediate-size automobile range sold in Japan and other countries. The 1989 model was introduced initially as a 4-door sedan, however a wagon was later produced. A large proportion were equipped with automatic transmissions....

  • Infiniti G35x/G37x
    Infiniti G
    The Infiniti G is a compact executive/entry-level luxury car produced by Nissan's luxury brand Infiniti. The first two generations of the Infiniti G were sedans based on the Nissan Primera. Beginning with its third generation , the Infiniti G have been rebadged versions of the Nissan Skyline line...

    /Nissan Skyline (V35 & V36)
  • Infiniti M35x/45x/37x/56x
    Infiniti M
    The "M" nameplate has been used on various mid-luxury cars from the Infiniti luxury division of Nissan.The first iteration was the M30 Coupe/Convertible, which were rebadged JDM Nissan Leopard....

    /Nissan Fuga
    Nissan Fuga
    The Fuga is a full-size sedan, rear wheel drive with optional all wheel drive, produced by Nissan of Japan since October 2004 and now in its second generation. It is built on a wider, stretched wheelbase version of the Nissan FM platform. After the Nissan Cima and Nissan President were...

  • Infiniti FX
    Infiniti FX
    The Infiniti FX is a mid-size luxury crossover SUV produced by the Nissan-owned Infiniti luxury vehicle brand since the 2003 model year. The FX replaced the QX4 as Infiniti's mid-size luxury-type SUV, although the QX4 was smaller than the FX. It was released at the same time as its competitors,...

  • Infiniti EX
    Infiniti EX
    The Infiniti EX is a premium-type compact crossover SUV priced below the Infiniti FX. It is based on the same FM platform as the Infiniti G, M, and FX models.- Infiniti EX Concept :...

    /Nissan Skyline Crossover (with Active Brake Limited Split for side-to-side torque split, as needed)
  • Nissan Cedric
    Nissan Cedric
    The Nissan Cedric is a large automobile produced by Nissan since 1960. It was developed to provide upscale transportation, competing with the Prince Skyline and Gloria which were later merged into the Nissan family...

     (Gloria\Cedric with RB25DET engine)


ATTESA E-TS Pro system is used in the following models:
  • R33 (1995-1997) Nissan Skyline GT-R
    Nissan Skyline GT-R
    The Nissan Skyline GT-R is a Japanese sports car based on the Nissan Skyline range.The first GT-Rs were produced from 1969–1973. After a 16 year hiatus since the KPGC110 in 1972, the GT-R name was revived in 1989 with the Skyline R32. This car was nicknamed "Godzilla" by the Australian motoring...

      (offered as a factory option)
  • R33 Nissan Skyline GT-R
    Nissan Skyline GT-R
    The Nissan Skyline GT-R is a Japanese sports car based on the Nissan Skyline range.The first GT-Rs were produced from 1969–1973. After a 16 year hiatus since the KPGC110 in 1972, the GT-R name was revived in 1989 with the Skyline R32. This car was nicknamed "Godzilla" by the Australian motoring...

      V-spec
  • R34 (1998-2002) Nissan Skyline GT-R
    Nissan Skyline GT-R
    The Nissan Skyline GT-R is a Japanese sports car based on the Nissan Skyline range.The first GT-Rs were produced from 1969–1973. After a 16 year hiatus since the KPGC110 in 1972, the GT-R name was revived in 1989 with the Skyline R32. This car was nicknamed "Godzilla" by the Australian motoring...

      (all models)


ATTESA E-TS Pro (GT-R version) is used in the following model(s).
  • 2008+ Nissan GT-R
    Nissan GT-R
    The Nissan GT-R is a sports car produced by Nissan released in Japan on December 6, 2007, the United States on July 4, 2008, and the rest of the world in March 2009.-History:...


See also

  • 4Matic
    4MATIC
    4Matic is the name of an AWD four-wheel drive system developed and used by Mercedes-Benz. It is designed to increase traction in slippery conditions....

     - a four-wheel drive system from Mercedes-Benz
    Mercedes-Benz
    Mercedes-Benz is a German manufacturer of automobiles, buses, coaches, and trucks. Mercedes-Benz is a division of its parent company, Daimler AG...

  • 4motion
    4motion
    4motion is a registered trademark of Volkswagen AG, used exclusively on Volkswagen-branded automobiles which utilise four-wheel drive systems. Volkswagen has previously used the term "Syncro" for its 4WD models....

     - a four-wheel drive system from Volkswagen
    Volkswagen
    Volkswagen is a German automobile manufacturer and is the original and biggest-selling marque of the Volkswagen Group, which now also owns the Audi, Bentley, Bugatti, Lamborghini, SEAT, and Škoda marques and the truck manufacturer Scania.Volkswagen means "people's car" in German, where it is...

  • All-Trac
    All-Trac
    All-Trac was a proprietary full time symmetric all wheel drive system used on a variety of Toyota badged models from 1988 to 2000. It was considered a revolutionary advance for all-wheel drive automobiles into the mainstream consumer market and its electronic/vacuum controlled locking center...

     - a four-wheel drive system from Toyota
  • Nissan Bluebird
    Nissan Bluebird
    Although Nissan's own materials indicate that the Bluebird name emerged in 1959, some records show that the name first adorned a 988 cc, four-door sedan in 1957, which was part of the company's 210 series...

  • Nissan Pulsar
    Nissan Pulsar
    The Nissan Pulsar is an automobile that was produced by the Japanese automaker Nissan from 1978, when it debuted as a subcompact car, to 2007, when it was replaced in all markets by the Nissan Tiida. It was originally conceived as a replacement for Nissan's first front-wheel drive platform, the...

  • Nissan Skyline
    Nissan Skyline
    The first Skyline was introduced in April 1957, by the Prince Motor Company, and was marketed as a luxury car. It featured a 1.5 L GA-30 engine producing 44 kW @ 4400 rpm. It used a de Dion tube rear suspension and was capable of 140 km/h . The car weighed around 1300 kg...

  • Nissan Skyline GT-R
    Nissan Skyline GT-R
    The Nissan Skyline GT-R is a Japanese sports car based on the Nissan Skyline range.The first GT-Rs were produced from 1969–1973. After a 16 year hiatus since the KPGC110 in 1972, the GT-R name was revived in 1989 with the Skyline R32. This car was nicknamed "Godzilla" by the Australian motoring...

  • Quattro (four wheel drive system) - a four-wheel drive system from Audi
    Audi
    Audi AG is a German automobile manufacturer, from supermini to crossover SUVs in various body styles and price ranges that are marketed under the Audi brand , positioned as the premium brand within the Volkswagen Group....

  • S-AWC - a torque vectoring four-wheel drive system from Mitsubishi Motors
    Mitsubishi Motors
    is a multinational automaker headquartered in Minato, Tokyo. In 2009 it was the fifth-largest Japan-based automaker and the 17th-largest in the world measured by production...

  • SH-AWD
    SH-AWD
    Super Handling-All Wheel Drive or SH-AWD is a full-time, fully automatic all-wheel drive traction and handling system designed and engineered by Honda Motor Company. The system was announced in April 2004, and first introduced in the North American market in the second generation 2005 model year...

     - a four-wheel drive system from Honda
    Honda
    is a Japanese public multinational corporation primarily known as a manufacturer of automobiles and motorcycles.Honda has been the world's largest motorcycle manufacturer since 1959, as well as the world's largest manufacturer of internal combustion engines measured by volume, producing more than...


External links

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