addicts. Dare I say it, some readers are actually researching, perusing, or attempting to garner an aficionado status. For these individuals, words and phrases like: forced induction; engine capacity; crossover; torque; direct shift gearbox, and other such things that are do not relate strictly to the automotive world, but when applied herein can become confusing. Confucius to the rescue, then. Rather, The Good Car Guy. When explanations are required, 'Answers' will be provided. Just email goodcarbadcar@gmail.com if there are more terms that boggle or baffle.
Considering The Good Car Guy's lack of engineering credentials and the likely lack of many readers' engineering qualifications, this 'Answers' page won't dig too deep. Just enough so that your next trip to GoodCarBadCar can be an enjoyable and understandable one. So, here's a few more terms that trip up the non-auto enthused.
REAR-WHEEL DRIVE, FRONT-WHEEL DRIVE, ALL-WHEEL DRIVE: Depending on where your reside, your next visit to a BMW, Cadillac, Lexus, Mercedes-Benz, or Chrysler showroom (amongst others) will be present you with an extra layer of decision making. You will have the option, while in the showroom, to select from a rear-wheel drive car, front-wheel drive car, or an all-wheel drive car. But what does all this mean? Well, take the BMW example.
Inside a BMW dealership, you can see a Mini Cooper, a BMW 328i, and a BMW 328xi. The Mini Cooper has a 1.6L four-cylinder engine with 118 bhp. (See yesterday's post if you don't follow.) All of that power flows from the engine, through the transmission; and to the front wheels. The front wheels then turn and pull the car forward.
Now for the 328i. This is the BMW brand's entry-level of sedans. This specific model has a 3.0L inline six cylinder with 230 horsepower. All of that power flows from the engine, through the transmission; and to the rear wheels. The rear wheels then turn and push the car forward.
But the BMW 328xi shows another story. BMW's specific all-wheel drive system is entitled xDrive. xDrive is consistently collecting information from sensors in and around the car. Steering angle, the car's rotation around its vertical axis, tire slip, and likely many other things - all enable xDrive to continuously apportion power to the wheels which need it most and can handle it best. That means all wheels. So, in the 328xi, the power is sent from the engine, through the transmission; and to any or all wheels. All wheels - or some wheels - work together to both pull and push the car forward. All-wheel drive systems from
other automakers like Audi, Subaru, and Infiniti, may work differently but accomplish the same result. Pulling and pushing. Audi is famous for their 'Quattro' badging, which signifies a car with all-wheel drive.There are benefits to each drive configuration. Front-wheel drive cars are obviously easier to package. The engine and its assorted hardware resides at the front, and only at the front. This creates the opportunity for an enlarged cabin. As you would assume, with passenger comfort and safety as a top priority, much of the world's automotive production is made up of front-wheel driven cars. Front-wheel drive cars demerits lie just where rear-wheel drive becomes beneficial.
Think about a husband and wife giving themselves two simple tasks. Wash the dishes and dry the dishes. If both husband and wife attempt to wash the dishes, the lack of sink space presents a gigantic problem. And the drying suffers. Likewise, a fwd car is tasked with sending the power through the front wheels while also forcing the front wheels to steer the car. If the rear wheels represented the husband; and simply washed(steered) ; while the front wheels represent the wife and simply dried (powered), then the operation would be smoother. What an odd analogy. Forgive me.
Herein lies the benefits of rear-wheel drive. The front wheels can be left to do their work. Wash the dishes. Er, rather, steer the car. The rear wheels can then propel the car forward. All-wheel drive, however, mixes and matches the benefits of both configurations. The added weight of the extra mechanicals required to power two axles is one downer. But added traction is inarguably a positive plus. Many AWD systems operate as front-wheel drive cars until those wheels slip. Then the rear wheels become aides to the cause. Pulling and pushing begins.
There aren't many true four-wheel drive vehicles kickin' around on dealer lots. Quite a few pickup trucks and the rugged sport-utility vehicles which stem from those pickups still offer the option of 4wd, that is, part-time; driver-selectable power sent to all four wheels or power being sent permanently to four wheels at 25% each.
Your drivetrain lesson is now complete. School's out for the weekend.
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