The Iconic Subaru Symmetrical All-wheel Drive, Explained

If you live somewhere snowy, you've probably considered an all-wheel drive vehicle. Subaru has perfected the all-wheel drive system to create a truly exceptional drive feel, no matter the conditions. All-wheel drive is great for more than just inclement weather. If you're cornering, accelerating hard or just driving around town, all-wheel drive can help keep you safe. Now, this doesn't mean during the freezing months you should forgo buying winter tires. Combine your all-wheel drive control, with the superior performance of winter tires, and you'll be able to tackle anything.

Unlike other all-wheel drive systems, Subaru integrates its transfer case into the transmission, as opposed to a front wheel bias. The use of limited slip differentials (LSD) is key, as they combine the benefits of open and locked differentials. The torque split of a LSD is based on available grip, and makes it a great choice for daily driving.

Subaru Employs Four Distinct Types of AWD Systems

They're all very similar, but subtle differences allow them to offer something for everyone.

Viscous Center Differential (VCD)

The simplest system of the bunch, but simple doesn't mean it's lacking in performance. This VCD system is used on all manual transmission models, like the Crosstrek, Impreza, and Forester. The torque is split 50/50 between the front and rear wheels and includes an open front and rear differential. If one wheel loses traction, the viscous coupling sends power to the wheels with more traction, allowing for greater grip and control.

Active Torque Split (ATS)

The next most popular option is the Active Torque Split system. Included on all continuously variable transmission (CVT) models like the Forester, Legacy and Outback, this option splits torque in a 60/40 ratio between the front and rear wheels. This AWD system includes a multi-plate center clutch, not a differential, but does have an open differential in the front and rear like in the VCD engine. It is called an Active system because unlike other AWD systems, it doesn't wait for loss of traction to engage, so there's no delay.

Variable Torque Distribution (VTD)

Only available on the CVT WRX, the VTD splits torque 45/55 between front and rear. This rear bias reduces understeer when accelerating hard. A Planetary center differential and an electronic hydraulic transfer clutch smoothly transfers power where you need it.

Driver Controlled Center Differential (DCCD)

Available only on the WRX STI, this drivetrain is the most advanced and sophisticated of the four. With a 41/59 split, it leans more on a rear bias, which is ideal for a sport-focused drive feel. Utilizing a planetary mechanical limited slip differential as well as an electronic differential that the driver can lock up when needed. In the front, there is a helical limited slip differential while in the rear you have a Torsen limited slip differential, as opposed to the others offering Open limited slip differentials in front and rear. Along with Active Torque Vectoring, a system that helps with cornering by applying brakes to the inside wheel to really hug you into a turn.

What Benefits Does Symmetrical All-Wheel Drive Offer?

• Grip
• Traction
• Handling
• Performance

Just to name a few things that you'll get when you choose a new Subaru from Quality Subaru. 

Power that's balanced between front and back, left and right, you'll have a consistent and predictable drive. Increased control, thanks to a consistent divide of power between all four wheels, allows for superior handling and cornering. Constantly evaluating which wheels have the most traction to maximize grip, no matter the conditions.

How They Differ from the Other FWD, FWD-Based AWD Systems and RWD Systems Offered by Competitors

Subaru Symmetrical All-wheel Drive is unique in that it is always active. Most other systems only provide power to the rear or front wheels when they are needed, like if the front wheels lose traction on an icy spot. Even though they offer a mild front or rear wheel bias, Subaru vehicles have power to all wheels, all the time. Most other systems have a consistent bias either way, and the differential is unable to send enough power to the needed wheels in the event of a loss of traction.

Why Choose a Subaru?

The benefits are almost endless. The superior technology extends far beyond just the drivetrain, and you'll feel it every time you sit behind the wheel. Test drive a new Subaru Outback, Impreza, Forester or any other model we have at Quality Subaru in Wallingford and you'll love the feeling of all-wheel drive control.