Drivetrain services encompass significant components that are important to the proper functioning of your vehicle. Without them, your car will not move. Collectively, these components are called the drivetrain.
The drivetrain consists of all parts that make the car go, excluding the engine. The engine is what is referred to as the powertrain, often confused with the drivetrain. Without it, a vehicle cannot transfer power and motion generated from the engine to rotate the wheels. There are three different types of drivetrains: Rear-wheel drive, front-wheel drive, and four-wheel/all-wheel drive. Each class has its components and mechanism of operation.
Rear-Wheel Drive Systems
For a while there, the rear-wheel drive system was the only drivetrain system available. Many European cars, especially BMW and Mercedes-Benz, use this type of set-up. It’s the reason why we have cool shots of vehicles peeling-out and drifting. Most importantly, it’s the reason enormous power can be transferred from the engine to the wheels.
The rear-wheel drive system comprises a transmission, drive shaft, and differential.
The need for a transmission, or gearbox, is to convert the output of the engine into a form that is better suited for the situation. For instance, engines operate anywhere between 600-700 RPM, while wheels rotate from zero to 1800 RPMs. Also, the engine provides uneven amounts of torque across the RPM range. So, the transmission helps control how to use the output of the engine. Transmissions, come in manual and automatic versions, with the latter dominating the market.
The drive shaft is merely a transmitter of torque over long distances, in this case, the transmission and rear wheels. The drive shaft is a long and circular tube and is needed in all types of drivetrain systems.
The differential sits between the two rear wheels and is the final step that converts the rotation of the driveshaft into the rotation of the wheels. It essentially turns the power 90 degrees to move the wheels and gets the car moving.
Front-Wheel Drive Systems
Front-wheel drive systems are found in most vehicles. It is popular in many minivans and sedans, like Audi and Volkswagen. The front-wheel-drive comprises of the transaxle (transmission) and half shaft (drive shaft).
The transaxle combines the differential and transmission, requiring the engine to be mounted sideways to make room.
Since all components of the system are up front, there is no need for a drive shaft. Only a half shaft is needed to connect the transaxle directly to the wheels.
Four-wheel and All-wheel Drive Systems
The use of four-wheel drive system is in off-road vehicles, agriculture tractors, and construction vehicles. The system transmits the power of the engine to each wheel individually and at different speeds, except when going in a straight line. The front-wheel system comprises the transmission, transfer case, front and rear drive shafts, and front and rear differentials.
The system is similar to rear-wheel drive systems, except that the transfer case splits the power between the rear and front drive shafts. Each drive shaft also operates individual differentials. The four-wheel drive system is the best at handling any terrain. However, the system adds weight and complexity, which increases costs and reduces fuel economy. Jeep popularized the four-wheeler with the Wrangler and Grand Cherokee, but today we see it in European SUVs like Audi, BMW, Mercedes-Benz, and Porsche.
If you would like to explore drivetrain systems in more detail, a great video can be watched on YouTube here.
European Service Center has 35 years of experience in services vehicles. Our highly trained ASE certified service mechanics have the tools to inspect, diagnose, and repair any drivetrain issue you may be having. Schedule your appointment today.