Do you know which wheels are used to propel your vehicle forward? The driven wheels play an important part in your vehicle’s handling dynamics.
Some vehicles can be ordered in multiple configurations, and each configuration has its own pros and cons. Keep reading to understand the differences between types of drivetrains and which one may be the best for you.
Related: AWD or 4WD (Which is Better?)
What is a Car’s Drivetrain?
Put simply, a drivetrain is every part of the powertrain that is used to provide forward motion to the vehicle, excluding the engine or electric motor(s) that generate the power. Some drivetrains send power to the front wheels only. Others send power only to the rear wheels, and some send power to both axles.
Components of the drivetrain include the torque converter, clutch, flywheel, transmission, driveshaft, axles, transfer case, and differential(s) where applicable.
Not all vehicles have all of these components. For example, a front-wheel drive vehicle will not have a transfer case, and manual transmissions do not use a torque converter.
Drivetrain vs Powertrain (What’s the Difference?)
The words “drivetrain” and “powertrain” are often used interchangeably but have different meanings.
The powertrain is the full system used to drive the vehicle forward, from the engine to the axles. Conversely, drivetrain refers to everything from the transmission back (including the flywheel or torque converter), but not the engine itself.
What is FWD?
FWD or front-wheel drive refers to any vehicle that is only driven by the front wheels. This is a common configuration in economy cars that use a transverse front-engine configuration.
FWD is particularly useful for economy cars due to its compact packaging and cost effectiveness. This is typically also the drivetrain configuration that suffers the fewest parasitic drivetrain losses, which means it tends to be the most fuel efficient choice.
What is RWD?
RWD or rear-wheel drive means all the power is sent to the rear wheels.
The biggest advantages to RWD are weight distribution and handling dynamics. Adding a rear differential to a vehicle shifts some of that vehicle’s weight rearward.
While front-engine, front-wheel drive cars tend to have a front-to-rear weight distribution of around 60/40, front-engine RWD cars tend to be much closer to 50/50. This allows the car to feel more balanced through turns, improving driving feel and handling at the limit of traction.
On a RWD car, the front wheels can focus primarily on turning and braking while the rear wheels focus on propelling the car forward.
Some of the most loved sports cars of all time, including the BMW M3 and M5, Chevrolet Corvette (C1-C7), Honda S2000, and Mazda MX-5 Miata use a front-engine rear-wheel drive layout.
If you like oversteer and want to take your car to the race track, RWD might be the right choice for you.
What is AWD?
AWD or “all-wheel drive” typically refers to any system where both the front and rear axles may receive power. Depending on the all-wheel drive system, both axles may not receive power 100% of the time.
A good AWD system gives you the most traction from a standstill. This gives you a substantial advantage if you drive up hills that frequently receive ice and snow; you’re less likely to slide backward down a hill when you step on the gas.
Subaru and Audi are both renowned for their quality all-wheel drive systems.
AWD also helps with aggressive launches, which may be particularly helpful if you’re interested in drag racing (or beating the guy next to you at the stoplight before your lanes merge).
Dual motor electric vehicles (such as Teslas with the “D” designation) have all-wheel drive. These vehicles use one electric motor for the front wheels and another for the rear.
See Also: “Check AWD System” Meaning
Do I Need All-Wheel Drive?
If you live in inclement weather, you may be wondering if upgrading to an all-wheel drive vehicle is worth it. The answer ultimately depends on how bad your weather gets and how flat your terrain is.
Do you encounter frequent snow, or are your winters primarily rainy? Rainy weather usually doesn’t call for AWD, and you may wish to pass up on AWD for the fuel and maintenance cost savings.
No matter which drivetrain you choose, nothing beats a quality set of winter tires. A RWD car on quality winter tires will almost always outperform an AWD car on all-season tires. Consider buying a second set of wheels and tires and switching them seasonally as weather permits.
What is 4WD?
4WD (also called 4×4 or 4-wheel drive) is sometimes used interchangeably with AWD.
Typically, 4WD refers to vehicles with a transfer case that allows the driver to manually engage and disengage power to the front axle. Computer controlled drivetrains or those that use a center differential instead of a transfer case are typically classified as AWD.
Most 4WD vehicles are body on frame trucks or Jeeps intended for rugged terrain. They may utilize a “locker” or locking differential on the front axle, rear axle, or both, in addition to their central transfer case.
What is the Most Common Type of Drivetrain?
Economy cars are the most mass produced vehicles in the world. Modern economy cars are typically found in the front-engine, front-wheel drive configuration. This saves cost and maximizes cargo capacity in the cabin.
FWD vehicles have no need to make room for a transmission or a driveshaft in the occupant space and typically have the fewest drivetrain components.
Which Drivetrain is Best For Inclement Weather?
The best vehicle for inclement weather is going to be the one that has the best tires for the situation at hand, not a particular drivetrain configuration.
Assuming all vehicles use the same tires, AWD is typically going to perform a bit better in bad weather because the torque is distributed across four tires instead of two.
Be aware that AWD only helps you get going; it does not help you turn or stop any faster. Stopping and turning is accomplished by the brakes and tires, not the drivetrain.
Which Drivetrain is Best Off Road?
Typically the best off road vehicles have a dedicated 4WD system and use lockers on the front and rear differentials. You will also need ample ground clearance and suspension travel.
If you’re rock crawling for instance, you need to be able to turn both wheels on an axle even if one of those wheels is in the air. This is something an open differential is unable to do without help from the traction control system.
Even if you have a sophisticated traction control system, it will not be quite as effective as a real locking differential.
Which Drivetrain is Best for the Race Track?
Although the answer to this question is a bit subjective, the general consensus is that rear-wheel drive makes the best driver’s car.
Rear-wheel drive tends to give you the most neutral handling characteristics. In other words, the front and rear tires will typically maintain similar levels of grip in a corner. This means the vehicle is not prone to excessive understeer or oversteer assuming a neutral throttle input.
Many drivers love to induce controlled oversteer on purpose, known as “drifting”. Some also enjoy burnouts and donuts, both of which are much easier with a high powered rear-wheel drive vehicle.
That said, you can put just about any road worthy car on an autocross course or race track if you really want to. Check out some of the strange vehicles filmed driving around the Nürburgring in Germany.
Which Drivetrain is Best For Road Trips and Daily Driving?
If you’re looking for an economical daily driver, FWD is your best bet. Modern FWD cars can attain 30-40 MPG or even more in some cases. They are also compact which makes them easier to park in big cities.
Nothing is more practical than a minivan. Most minivans maintain a FWD configuration to maximize efficiency and cargo space. Some vans come with AWD, but you may have to sacrifice a middle seat and some gas mileage to make room for the transmission or driveshaft.
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