4WD vs AWD

The difference between four-wheel drive (4WD) and all-wheel drive (AWD) can be a little vague. I read a lot of resources, and they waffle quite a bit.

In general:

• All-Wheel Drive requires no driver input. There’s a computer in the car that just makes it work. The car usually drives two wheels, but if the car detects slippage, it routes power to the two other wheels. Additionally, some vehicles can adjust power from left to right, with some being able to effectively send all the engine’s power to a single wheel.

• Four-Wheel Drive requires driver input. You are in two-wheel drive, until such time that you decide to go into four-wheel drive. 4WD drive vehicles often also have two common features:

  • A “low-range” which uses gearing to provide maximum power at low speed
  • “Locking” differentials and axles which force all the wheels to always rotate at the same speed

But there are edge cases where it gets weird. For instance, some 4WD vehicles are “full-time 4WD” which means they are always in 4WD. So…are they AWD? Maybe? But if they have a low-range and we can lock the axles, would we still call that 4WD?

I feel like “all-wheel drive” is a marketing term created because manufacturers wanted to make cars with all four wheels under power, but they didn’t want people to view them as trucks or off-road vehicles, so they invented a new, “softer” term.

To be sure, there’s a lot of crossover – some vehicles marketed as “4WD” have more in common with vehicles labeled AWD, and vice-versa.