If you hadn’t figured out which wheels were powering your vehicles as of yet (shame on you if you didn’t), Buick is offering a lesson in drivetrains for those of you looking for more insight into how front-wheel, rear-wheel and all-wheel drive work in concert with your vehicle to offer you uniquely different driving experiences.
Front-wheel drive, or FWD, by far has become the most prominent choice from auto manufacturers, mostly because of its small packaging to enhance fuel economy. The biggest advantage to FWD vehicles, though, is the weight of the powertrain sits above the driving wheels, offering greater traction during slippery and wet conditions.
Then we arrive at the standard in performance drivetrains, RWD. Power is sent, obviously, to the rear wheels and can effectively handle higher engine power and more heft from vehicle weight. As we’ve seen over the past few decades, RWD has slowly been phased out in favor of FWD platforms with AWD variations. RWD today is normally saved for performance duties and large trucks.
But let’s not forget the rust belt’s favorite option, all-wheel drive. AWD operates as either a FWD or RWD system, and power is sent to the front and rear axles to prevent wheel slip, but backs the power off if computer systems see their is no slippage occurring. Power is transferred automatically via a single-speed transfer case, which allows the transmission to split the power between the rear and front wheels. All-wheel drive allows for seamless power transition without any input or activation from the driver. AWD is currently offered the Regal, LaCrosse, Encore and Enclave.
Finally, not to be confused with all-wheel drive, four-wheel drive, or 4×4, allows for maximum traction with a two-speed transfer case with high and low ranges. Although not found on any Buicks, GM offers a handful of the products with 4×4 for the best capability in slick conditions.