CVT: A shift away from gears
A Continuously Variable Transmission (CVT) is an automatic transmission that doesn’t use gears, instead relying on a belt, chain and pulleys to transfer power to the driven wheels. As it has no physical gears or fixed gear ratios, a CVT actually features the equivalent of an infinite number of gears. This characteristic, in turn, provides advantages in terms of acceleration, smoothness, fuel efficiency and eco-friendliness. The Lineartronic® CVT has proven so well suited to the SUBARU BOXER engine and Subaru symmetrical full-time All-Wheel Drive, it has replaced most traditional automatic transmissions in the Subaru line-up.
Benefits of the Lineartronic CVT
Less wear and tear
One of the biggest benefits of a CVT is that wear and tear on the transmission is minimal compared to the wear that takes place in a traditional transmission with set gears. The CVT requires fewer moving parts and this means that there’s less friction and less heat working on the parts, wearing them down.The only maintenance required is changing fluids every 100,000 km, so you’ll also benefit from less wear and tear on your wallet.
Linear acceleration and overall performance
When accelerating in a vehicle with a typical manual or automatic transmission, the act of changing of gears interrupts the process — there’s always some degree of shift delay. For example, when going uphill on a highway an automatic transmission may hunt between gears trying to find the best compromise between fuel economy and power. The shift delay in this instance means the engine has to work harder immediately after an upshift to get the vehicle up to speed again. When downshifting with a manual transmission, an engine will often over-rev when a lower gear is selected, potentially leading to engine failure. The constant, step-less acceleration of the Lineartronic CVT eliminates shift delay altogether, generates smooth, linear acceleration and boosts drivetrain efficiency. In automatic mode, adaptive shift logic ensures the optimal ratio is selected to suit any situation, while a stepped variable control responds to changes in engine speed, maximizing driveability. In manual mode, ratios are selected through paddle shifters mounted behind the steering wheel. The result: a sharper, sportier and more responsive driving experience overall.
Improved fuel economy and lower emissions
The Lineartronic CVT is engineered to work seamlessly with the SUBARU BOXER® engine and Subaru symmetrical full-time AWD to help reduce consumption and, in many cases, match the fuel efficiency of FWD vehicles in the same classes. The secret: This transmission keeps the vehicle in its optimum power range, regardless of vehicle speed, and it allows the engine to operate at lower revs to save on fuel. When a conventional automatic transmission shifts, the interruption in power and the “shift shock” that takes place when the next gear is taken both negatively impact fuel efficiency. Rather than using set gear ratios, a CVT continuously varies the gear ratio, completely eliminating shift delays and shift shock — while keeping the vehicle in its optimum fuel efficiency range. As the Lineartronic offers better control of engine speed range, it also has more control over emissions. In fact, this CVT is designed to comply with future environmental standards for CO2 emissions.
How a CVT works… and why the Lineartronic is a better CVT
After years of research and development, Subaru engineers were able to introduce a production-car first: a CVT longitudinally paired with AWD that uses a chain instead of the more commonly used belt. Thanks to this unique design, the Lineartronic CVT uses smaller pulleys, making it lighter and more efficient overall. This design also boasts a more natural feel as compared to other CVTs, allowing drivers to experience instant response that is also smoother and quieter.
This CVT employs two hydraulically actuated, adjustable V-shaped pulleys that are connected via the chain. Depending on vehicle speed, the pulley sides are pushed in or pulled out, which causes the chain to move through “the valley” created by the pulleys. The chain moves seamlessly, which means there is no interruption in power and this translates into smoother acceleration, improved fuel efficiency and lower emissions. The CVT operates automatically, but those looking for a more involving experience can opt for the six-speed manual mode. These preset ratios can be selected using the paddle shifters mounted on the steering column, allowing the driver to control when and how the pulleys move. This feature gives the driver a sportier driving experience as an added benefit.