ATTESA (acronym for Advanced Total Traction Engineering System for All-Terrain) is a
four-wheel drive
Four-wheel drive, also called 4×4 ("four by four") or 4WD, refers to a two-axled vehicle drivetrain capable of providing torque to all of its wheels simultaneously. It may be full-time or on-demand, and is typically linked via a transfer case ...
system used in some
automobiles
A car or automobile is a motor vehicle with wheels. Most definitions of ''cars'' say that they run primarily on roads, seat one to eight people, have four wheels, and mainly transport people instead of goods.
The year 1886 is regarded as ...
produced by the Japanese automaker
Nissan
, trade name, trading as Nissan Motor Corporation and often shortened to Nissan, is a Japanese multinational corporation, multinational Automotive industry, automobile manufacturer headquartered in Nishi-ku, Yokohama, Japan. The company sells ...
, including some models under its luxury marque
Infiniti
is the luxury vehicle division of the Japanese automaker Nissan. Infiniti officially started selling vehicles on November 8, 1989, in North America. The marketing network for Infiniti-branded vehicles included dealers in over 50 countries in ...
.
The 'mechanical' ATTESA system was developed for
transverse
Transverse may refer to:
*Transverse engine, an engine in which the crankshaft is oriented side-to-side relative to the wheels of the vehicle
*Transverse flute, a flute that is held horizontally
* Transverse force (or ''Euler force''), the tangen ...
layout vehicles and introduced with the RNU12
Bluebird
The bluebirds are a North American group of medium-sized, mostly insectivorous or omnivorous birds in the order of Passerines in the genus ''Sialia'' of the thrush family (Turdidae). Bluebirds are one of the few thrush genera in the Americas.
...
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 transmission combinations. An almost identical system is fitted to the RNN14 GTi-R
Pulsar
A pulsar (from ''pulsating radio source'') is a highly magnetized rotating neutron star that emits beams of electromagnetic radiation out of its magnetic poles. This radiation can be observed only when a beam of emission is pointing toward Ea ...
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 center
viscous
The viscosity of a fluid is a measure of its resistance to deformation at a given rate. For liquids, it corresponds to the informal concept of "thickness": for example, syrup has a higher viscosity than water.
Viscosity quantifies the inter ...
limited slip differential
A limited-slip differential (LSD) is a type of differential that allows its two output shafts to rotate at different speeds but limits the maximum difference between the two shafts. Limited-slip differentials are often known by the generic tr ...
, into a transfer case splitting drive to a co-located front differential, and tail shaft connected to the vehicle's rear
differential.
From 2000 model year onwards, the system received an update where, as with a typical
FWD car, the
transaxle
A transaxle is a single mechanical device which combines the functions of an automobile's transmission, axle, and differential into one integrated assembly. It can be produced in both manual and automatic versions.
Engine and drive at the ...
now contained a differential that drives the front wheels. However, an extra shaft from this differential also drives a
bevel gear
Bevel gears are gears where the axes of the two shafts intersect and the tooth-bearing faces of the gears themselves are conically shaped. Bevel gears are most often mounted on shafts that are 90 degrees apart, but can be designed to work at oth ...
housed in the transfer case that permanently turns a
driveshaft
A drive shaft, driveshaft, driving shaft, tailshaft (Australian English), propeller shaft (prop shaft), or Cardan shaft (after Girolamo Cardano) is a component for transmitting mechanical power and torque and rotation, usually used to connect ...
for the rear wheels (i.e. there is no longer a "center" 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 since the standard operation is
FWD there is less power lost due to friction. However, it is no longer a full-time 4WD system, and since the coupling is in the rear differential, the driveshaft itself is constantly driven even though it is not connected to anything, which saps some power and efficiency (the analogue being the front driveshaft of a
part-time 4x4 truck without
locking hubs
Locking hubs, also known as free wheeling hubs are fitted to some (mainly older) four-wheel drive vehicles, allowing the front wheels to rotate freely when disconnected (unlocked) from the front axle. This is done to reduce the mechanical resist ...
).
Variations
E-TS
The Electronic Torque Split version of this all-wheel drive architecture is a more advanced 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 GTS-4. Although the Skyline GT-R is exclusively AWD with manual transmission, ATTESA E-TS is also used in Nissan models that are available as rear wheel drive (RWD) 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
The Nissan FM platform is a modern FR automobile layout. The name is derived from the " front midships" location of the engine, with its center of mass located behind the front axle centerline, shifting weight to the middle of the car, leaving the ...
(which are sold in certain markets under the
Infiniti
is the luxury vehicle division of the Japanese automaker Nissan. Infiniti officially started selling vehicles on November 8, 1989, in North America. The marketing network for Infiniti-branded vehicles included dealers in over 50 countries in ...
luxury brand).
The ATTESA E-TS version uses a mostly conventional RWD transmission. Drive to the rear wheels is constant via a tailshaft and rear
differential, but drive to the front wheels is more complex by utilizing a
transfer case
A transfer case is a part of the drivetrain of four-wheel-drive, all-wheel-drive, and other multiple powered axle vehicles. The transfer case transfers power from the transmission to the front and rear axles by means of drive shafts. It also syn ...
on the rear of the transmission.
The drive for the front wheels comes from a transfer case bolted on the end of an almost traditional Nissan RWD transmission. 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
A clutch is a mechanical device that engages and disengages power transmission, especially from a drive shaft to a driven shaft. In the simplest application, clutches connect and disconnect two rotating shafts (drive shafts or line shafts). ...
pack in the transfer case
"differential" (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
The Porsche 959 is a sports car manufactured by German automobile manufacturer Porsche from 1986 to 1993, first as a Group B rally car and later as a road legal production car designed to satisfy FIA homologation regulations requiring at least 2 ...
. This unit is lubricated with its own dedicated NS-ATF fluid supply (Nissan Special Automatic Transmission Fluid) and is not in any way connected to the fluid in the transmission. Some Nissan models have an external cooler with an electric pump to cool this fluid.
Situated on top of the rear differential is a high pressure, low volume electric pump. This pump pressurizes Normal ATF (0-288 psi) into the transfer case to engage the clutch pack. This fluid only engages the clutch pack and does not mix with the NS-ATF lubricating the transfer case. The higher the fluid 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 differential made as a single unit that cannot be separated. The front right axle is shorter than the left, because the differential is closer to the right wheel. The front left axle runs through the engine's sump to the left wheel.
To control the ATTESA E-TS system, there is a 16-bit computer that monitors the cars movements 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 a computer, which controls both the ATTESA-ETS AWD system and the ABS system. The computer can then direct up to 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-limited slip differential. Rather than locking the AWD in all the time or having a system that is "all or nothing", the ATTESA E-TS system can apportion different
torque
In physics and mechanics, torque is the rotational equivalent of linear force. It is also referred to as the moment of force (also abbreviated to moment). It represents the capability of a force to produce change in the rotational motion of th ...
ratios 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 the factory, the system is set up to provide slight oversteer in handling, and in fact the harder the car is cornered, the LESS the AWD 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
A limited-slip differential (LSD) is a type of differential that allows its two output shafts to rotate at different speeds but limits the maximum difference between the two shafts. Limited-slip differentials are often known by the generic tr ...
) system is response in hundredths of a second.
Some models fitted with the ATTESA E-TS system (such as the Nissan RS4 Stagea) have a "S" button on the dash. This will bypass the control system of the ATTESA E-TS computer and lock the transfer case into full 4WD. This is to be used at low speeds in snowy/icy conditions only as understeer is greatly increased in this mode.
E-TS 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 & R34 Skyline GT-R V.spec (Victory Specification) model, and was offered as an option on the standard Skyline GT-R models called the "Active
LSD
Lysergic acid diethylamide (LSD), also known colloquially as acid, is a potent psychedelic drug. Effects typically include intensified thoughts, emotions, and sensory perception. At sufficiently high dosages LSD manifests primarily mental, vi ...
option". The active rear
LSD
Lysergic acid diethylamide (LSD), also known colloquially as acid, is a potent psychedelic drug. Effects typically include intensified thoughts, emotions, and sensory perception. At sufficiently high dosages LSD manifests primarily mental, vi ...
was also available as an option on some rear wheel drive Nissans such as the R33 GTS25t and C34 RS Stagea.
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 system is also capable of left-and-right torque split to the rear wheels. This is done via an active rear
LSD
Lysergic acid diethylamide (LSD), also known colloquially as acid, is a potent psychedelic drug. Effects typically include intensified thoughts, emotions, and sensory perception. At sufficiently high dosages LSD manifests primarily mental, vi ...
. Additionally, ATTESA E-TS Pro was marketed as controlling the ABS system to each wheel independently, while the previous ABS computer could sense the speed of each wheel its ABS pump is only 3-channel (both rear brakes are linked as a pair). Although this is not part of the AWD system, the computer 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.
The R33 Skyline regularly updates the speed of the rear wheels to the wheel speed sensors 100 times per second while the R34 Skyline regularly updates the speed of the rear wheels to the wheel sensors 1,000 times per second.
The 2009
Nissan GT-R
The Nissan GT-R (Japanese: 日産・GT-R, ''Nissan GT-R''), is a high-performance sports car and grand tourer produced by Nissan, unveiled in 2007. It is the successor to the Skyline GT-R, a high performance variant of the Nissan Skyline. Alth ...
uses an updated version of the ATTESA E-TS, which is designed to work with the car's rear transaxle layout. The system is unique in the way that it utilizes two driveshafts under the vehicle's centerline, with a second driveshaft running slightly to the right of the main driveshaft which transfers power to the front wheels.
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-to-rear torque split can go from 2:98 during a standing start to a maximum of 50:50
2008 Nissan GT-R - Engine and AWD System - First Look - Motor Trend
/ref>
Models and types
ATTESA E-TS system is used in the following models:
* R32 and R33 (1989–1997) GT-R, GTS-4 Skyline
* 1990–1994 Nissan Cefiro SE4, LNA31
* Nissan Skyline GT-R
The is a sports car based on the Nissan Skyline range. The first cars named "Skyline GT-R" were produced between 1969 and 1972 under the model code KPGC10, and were successful in Japanese touring car racing events. This model was followed by ...
- 1989–2003
* Nissan Stagea
The Nissan Stagea is a station wagon produced by Nissan from 1996 to 2007. It was originally produced by Nissan in 1996 as direct competition for the Subaru Legacy Touring wagon in Japan, and was exclusive to '' Nissan Prince Store'' Japanese ...
* Nissan Laurel
The Nissan Laurel is a front-engine, rear-drive two- and four-door sedan manufactured and marketed by Nissan from 1969 to 2002. Introduced in 1968 as a new model positioned above the 1968 Datsun Bluebird 510, the Laurel offered the luxury of the ...
C34 (1994-1997) and C35 (1997–2002)
* 1997–2003 Infiniti QX4
* Infiniti G35x/G25x/G37x/ Nissan Skyline (V35 & V36)
* Infiniti M35x/45x/37x/56x/Nissan Fuga
The Nissan Fuga (Japanese: 日産・フーガ ''Nissan Fūga'') is a mid-size luxury sedan produced by Japanese automaker Nissan since October 2004. It is built on a wider, stretched wheelbase version of the Nissan FM platform. After the Nissan C ...
* Infiniti QX70
The Infiniti QX70, formerly called the Infiniti FX until 2013, is a mid-size luxury crossover SUV produced by the Nissan-owned Infiniti luxury vehicle brand between 2002 and 2017. The FX replaced the QX4 as Infiniti's mid-size SUV. It shares the ...
* Infiniti EX
The Infiniti QX50, previously the Infiniti EX or Nissan Skyline Crossover until 2013, is a compact luxury crossover SUV produced by Infiniti, the luxury vehicle division of Japanese automaker Nissan. The first-generation QX50 is a minor model upd ...
/Nissan Skyline Crossover
The is a brand of automobile originally produced by the Prince Motor Company starting in 1957, and then by Nissan after the two companies merged in 1967. After the merger, the Skyline and its larger counterpart, the Nissan Gloria, were sold in ...
(with Active Brake Limited Split for side-to-side torque split, as needed)
* Nissan Cedric
The 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. In later years, the Nissan Skyline was posi ...
(Gloria/Cedric with RB25DET engine)
* Nissan Skyline Sedan 350GT FOUR Hybrid/Infiniti Q50
The Infiniti Q50 is a compact executive car manufactured by Nissan for its luxury brand, Infiniti. Replacing the G/Q40 sedan, it debuted at the 2013 North American International Auto Show and went on sale in North America in the third quarter ...
ATTESA E-TS Pro system is used in the following models:
* R33 (1995–1997) Nissan Skyline GT-R
The is a sports car based on the Nissan Skyline range. The first cars named "Skyline GT-R" were produced between 1969 and 1972 under the model code KPGC10, and were successful in Japanese touring car racing events. This model was followed by ...
(offered as a factory option)
* R33 Nissan Skyline GT-R
The is a sports car based on the Nissan Skyline range. The first cars named "Skyline GT-R" were produced between 1969 and 1972 under the model code KPGC10, and were successful in Japanese touring car racing events. This model was followed by ...
V-spec
* R34 (1998–2002) Nissan Skyline GT-R
The is a sports car based on the Nissan Skyline range. The first cars named "Skyline GT-R" were produced between 1969 and 1972 under the model code KPGC10, and were successful in Japanese touring car racing events. This model was followed by ...
(all models)
* 2008+ Nissan GT-R
The Nissan GT-R (Japanese: 日産・GT-R, ''Nissan GT-R''), is a high-performance sports car and grand tourer produced by Nissan, unveiled in 2007. It is the successor to the Skyline GT-R, a high performance variant of the Nissan Skyline. Alth ...
(different implementation)
See also
* 4Matic
4Matic (stylized as 4MATIC'') ''is the marketing name of an all-wheel drive system developed by Mercedes-Benz. It is designed to increase traction in slippery conditions. With the introduction of the 2017 E 63 S sedan, Mercedes-AMG announced a p ...
- a four-wheel drive system from Mercedes-Benz
Mercedes-Benz (), commonly referred to as Mercedes and sometimes as Benz, is a German luxury and commercial vehicle automotive brand established in 1926. Mercedes-Benz AG (a Mercedes-Benz Group subsidiary established in 2019) is headquartere ...
* 4motion - a four-wheel drive system from Volkswagen
Volkswagen (),English: , . abbreviated as VW (), is a German Automotive industry, motor vehicle manufacturer headquartered in Wolfsburg, Lower Saxony, Germany. Founded in 1937 by the German Labour Front under the Nazi Party and revived into a ...
* All-Trac - a four-wheel drive system from Toyota
is a Japanese multinational automotive manufacturer headquartered in Toyota City, Aichi, Japan. It was founded by Kiichiro Toyoda and incorporated on . Toyota is one of the largest automobile manufacturers in the world, producing about 10 ...
* Nissan Bluebird
The is a compact car with a model name introduced in 1957. It has been Nissan's most internationally recognized sedan, in multiple body styles, and is known for its dependability and durability. The Bluebird originated from Nissan's first vehic ...
* Nissan Pulsar
The is a line of automobiles produced by the Japanese automaker Nissan from 1978 until 2000, when it was replaced by the Nissan Bluebird Sylphy in the Japanese market.
Between 2000 and 2005, the name "Pulsar" has been used in Australia and New ...
* Nissan Skyline
The is a brand of automobile originally produced by the Prince Motor Company starting in 1957, and then by Nissan after the two companies merged in 1967. After the merger, the Skyline and its larger counterpart, the Nissan Gloria, were sold in ...
* Nissan Skyline GT-R
The is a sports car based on the Nissan Skyline range. The first cars named "Skyline GT-R" were produced between 1969 and 1972 under the model code KPGC10, and were successful in Japanese touring car racing events. This model was followed by ...
* Nissan GT-R
The Nissan GT-R (Japanese: 日産・GT-R, ''Nissan GT-R''), is a high-performance sports car and grand tourer produced by Nissan, unveiled in 2007. It is the successor to the Skyline GT-R, a high performance variant of the Nissan Skyline. Alth ...
* Quattro (four wheel drive system)
quattro (meaning ''four'' in Italian language, Italian) is the trademark used by the Automotive industry, automotive brand Audi to indicate that all-wheel drive (AWD) technologies or systems are used on specific models of its automobiles.Audi. ...
- a four-wheel drive system from Audi
Audi AG () is a German automotive manufacturer of luxury vehicles headquartered in Ingolstadt, Bavaria, Germany. As a subsidiary of its parent company, the Volkswagen Group, Audi produces vehicles in nine production facilities worldwide.
Th ...
* S-AWC
S-AWC (Super All Wheel Control) is the brand name of an advanced full-time four-wheel drive system developed by Mitsubishi Motors. The technology, specifically developed for the new 2007 Lancer Evolution, - a torque vectoring four-wheel drive system from Mitsubishi Motors
is a Japanese multinational automobile manufacturer headquartered in Minato, Tokyo, Japan.[SH-AWD
Super Handling-All Wheel Drive (SH-AWD) is a full-time, fully automatic, all-wheel drive traction and handling system combining front-rear torque distribution control with independently regulated torque distribution to the left and right rear whe ...](_blank)
- a four-wheel drive system from Honda
is a Japanese public multinational conglomerate manufacturer of automobiles, motorcycles, and power equipment, headquartered in Minato, Tokyo, Japan.
Honda has been the world's largest motorcycle manufacturer since 1959, reaching a product ...
* Symmetrical All Wheel Drive
The Symmetrical All-Wheel Drive (also known as Symmetrical AWD or SAWD) is a full-time four wheel drive, four-wheel drive system developed by the Japanese automobile manufacturer Subaru. The SAWD system consists of a longitudinally mounted flat eng ...
- the four wheel drive system from Subaru
( or ; ) is the automaker, automobile manufacturing division of Japanese transportation conglomerate (company), conglomerate Subaru Corporation (formerly known as Fuji Heavy Industries), the Automotive industry#By manufacturer, twenty-first ...
References
External links
Car Information Database (Nissan)
Nissan Bluebird Car Club NZ
{{DEFAULTSORT:Attesa
Nissan
Four-wheel-drive system tradenames