When shopping for an SUV or truck, or even a Subaru, you’ll see one of two terms, AWD or 4WD, as an option. While both are good for different things, they aren’t always necessary, and knowing how they work and what they’re for helps with the decision process when choosing a car to buy. Also if you’re going to be dealing with snow, you’ll most likely want one of these as an option. RWD is probably the worst configuration for driving in the snow, as no power goes to the front of the car. Bear in mind that trucks are usually RWD, and while most will have a 4WD option it’s not always standard, so be sure to get the 4WD when if you’re shopping for a new truck in a snowy area.
Car differentials usually send power to two wheels, and that means power from the engine is only going to one side of the car, and the performance difference between the two is vastly different. In a rear wheel drive car, power goes from the engine to the rear wheels, whereas in a front wheel drive car the power goes to the front wheels via what’s called a transaxle, which is a transmission and differential as part of one single unit. An AWD car has both a rear axle for RWD, and a transaxle for FWD, and connects the two with a third, “Center” differential. At all times, with AWD, all four wheels are getting power. There’s more drivetrain loss with AWD than with RWD and FWD, but the upshot is AWD layouts have more grip, which is one of the reasons it helps in the snow.
4WD is similar to AWD in that it provides power to two axles, or all four wheels, but does so with what’s called a transfer case and can be used on demand. In trucks and off-road vehicles like Jeep Wranglers, 4WD is a mode you can select, sometimes with a gearshift. When it’s selected, there’s a separate range of gears for driving all four wheels, usually denoted with “Low” or “High” selections, indicating low or high gears. There are two kinds of transfer cases, chain driven or gear driven. While chain driven transfer cases are lighter, gear driven are more durable. 4WD is great for trucks because using all four wheels make the fuel efficiency worse, so being able to turn it off and on at will helps a great deal, whereas with AWD you wouldn’t have a choice.
If you’re someone who lives in the snow and prefers a smaller more economical car than a truck, Subaru’s AWD system is hard to overlook. The Subaru has a hard time staying stuck, whereas other AWD systems will choose when to activate all four wheels in order to save fuel, or, be more fuel efficient. Subaru’s AWD is always active, which makes it less complicated.
For needing a truck, a 4WD diesel like a Dodge RAM is the best way to go. The older Cummins Turbo Diesel trucks from early-mid 2000s are tried and true workhorse machines, they are powerful and reliable even in the snow.
We’d have to say that it depends more on the vehicle than the type of drivetrain. If you need to get a truck for hauling things around and need to get through the snow then 4WD is the way to go. However, if you’re more into commuting and joy rides through the snow, you can get away with a smaller car equipped with AWD. Trucks need the option in that kind of environment, but when you don’t need that kind of traction it becomes very inefficient. You always want either AWD or 4WD in the snow, it just depends on what you’re going to use the car for.
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