Front-wheel-drive is commonly shortened to FWD and is a type of transmission/engine arrangement used for cars and trucks. It primarily refers to the way the engine controls your front wheels. Many times, it includes a transverse engine rather than a traditional layout, called a longitudinal engine. While longitudinal engines are highly popular for rear-wheel and four-wheel drive vehicles, the transverse engine primarily uses FWD.
Throughout the years, there have been three primary engine setup categories. It can be helpful to learn more about them.
Transversely Mounted: The first FWD vehicle with a transverse engine was the DKW Front F1, designed in 1931. The engine was a two-stroke twin cylinder. Saab then copied that design to use in their Saab 92. Some vehicles with a transversely mounted engine use four-cylinders and inline water cooling. These can include the Allegro, Mini of Issigoni (1959), Maxi, Austin 1100/1300, Peugeot 104, Renault 14 or the Datsun 100A (cherry). In this arrangement style, the transmission goes under the crankshaft in the sump while the transfer gears provide the power.
You can also find a transmission that sits beside the transverse engine, such as the Fiat 127 and 128 or the Autobianchi Primula (1964). They usually put the transmission in front of its differential which double backs the drivetrain. Of course, it also causes an irregular shape to the driveshaft and wheels, as one side is invariably longer than the other. It has become highly popular around the world.
Longitudinally Mounted: With this type of mounting, the engine is put before the wheels in the front and the transmission. The differential, meanwhile, is put in the back assemblage. Of course, there is a primary disadvantage of design because of poor weight distribution. However, many vehicles used this option, especially in early years. However, Audi still uses this arrangement in many of their vehicles. It’s applied primarily to the larger models, including the A4. Their solution to the weight problem was to put the clutch behind its differential and move the front axle line forward.
Mid-Engine: Of course, the first four-wheel-drive vehicle wasn’t called FWD. It was actually called a mid-engine with a front-wheel-drive layout, sometimes called an MF. The earliest vehicle with this arrangement had wheels in front of an engine that was longitudinally installed, though the transmission was far away from the engine and the differential was in the front of the car. Of course, it was an inconvenient location because of uneven weight distribution. Therefore, the car’s wheels didn’t handle the best or have excellent traction. They solved the problem by putting the differential close to the middle and putting the transmission closer to the front.
Since about 1990, front-wheel-drive keeps getting more innovative and better. Newer vehicles still use the arrangement because it works. Of course, transversely-installed engines are highly popular. Other features to go with the design of the engine include electronically-controlled cooling fans, driveshafts with constant velocity, CV joints for the front wheels, and end-on mounting for the transmission.
It should be noted that Volvo changed most of their car models to FWD after their launch of the 900 series. Their primary reason was for safety, as the transversely installed engine had a larger crumple zone, which allowed more protection during head-on collisions. However, most American carmakers prefer rear-wheel-drive for large vehicle models because of better handling. However, it should be noted that FWD versions are more fuel-efficient, cheaper to manufacture, and smaller.