Well if you live in the north of the country (or are a friendly neighbor to the north, or if you’re soon-to-be Canadian because of the election) it’s that time of year again. The leaves feel from the trees and the cold white stuff didn’t wait around. Since yesterday was the first snowfall around here, including some snow days for upstate schools, anyone in the market for a new car may want to take the powertrain layout into consideration. If you know little about automobile powertrain layout, this should be a decent read.

Well if you live in the north of the country (or are a friendly neighbor to the north, or if you’re soon-to-be Canadian because of the election) it’s that time of year again. The leaves feel from the trees and the cold white stuff didn’t wait around. Since yesterday was the first snowfall around here, including some snow days for upstate schools, anyone in the market for a new car may want to take the powertrain layout into consideration. If you know little about automobile powertrain layout, this should be a decent read.

Front Wheel Drive (FWD)

Front wheel drive (FWD) has been the standard for as long as I can
remember. Again it goes back to that whole economobile concept
mentioned here.
Low displacement engines can be mounted transversely in the engine
compartment which puts the power on the front wheels, along with the
added benefit of weight to those wheels. While FWD gives a high amount
of assurance in snowy conditions it is by no means perfect. While
generally these cars are considered two wheel drive, they are actually
one wheel drive. If you ever manage to put one tire off the driveway
and get stuck, you’ll know what I mean. The most obvious benefit of
FWD relates to the physics of being “pulled” as opposed to “pushed.”
With the front end doing the powering and the steering, it’s quite
difficult to whip the car’s tail around - not impossible, but
definitely not easy. The biggest disadvantage to FWD is the added
complexity of having the drive wheels steer, as well as the size
limitations of the engine compartment and thus, difficulty of service.

Rear Wheel Drive (RWD)

Rear wheel drive (RWD) used to be a more common layout, and may god
forbid that you should drive one of these beasts in Upstate NY (*hack,
cough*). Nowadays RWD is mostly reserved for beefier cars or trucks,
and driving can be a bit hairy in nasty situations. Again, let’s
revisit high school physics class. If the power is coming from the
back and the front wheels are sliding more than their turning, it’s
really easy to whip the tail around (test this on your own by pushing
a pen on your desk from both the front and the back to compare if
you’ve never owned RWD). In personal experience, this is most common
at speeds under 30 mph, which generally results from having to follow
people in AWD Suburus that don’t understand that their AWD is capable
of handling more than 30. If you service your own vehicle, RWD engines
are much easier to work on than FWD.

However, given the recent RWD boon, most companies have some sort of
electronic traction control, from which many RWD vehicles can
outperform or perform equally as well in wet conditions as FWD
(Source: Popular
Mechanics). I’d also suggest you pick up a subscription to that
mag.

You may remember the part where I said that most cars are one wheel
drive. This is not always true however, as you know if you’ve ever
watched My Cousin Vinny. Often when purchasing a truck you can option
in a “Limited Slip Differential,” which may also be known amongst
other things as Positraction (My Cousin Vinny reference now complete).
The limited slip differential actually makes your truck true two wheel
drive, as both wheels will turn when one slips. It’s a handy tool for
towing, and can also be used on sports cars to limit burnouts.

All Wheel Drive (AWD)

All wheel drive (AWD) is the reason that your mother bought her brand
new SUV. Did she really need an SUV? Nope. If you want the
benefits of AWD without buying your own personal gas station, Audi has
made cars with their Quattro(TM) system for quite some time. Not be
left out of the mix, Suburu has also popularized the AWD phenomenon
with the overwhelming success of the WRX (That car was so much cooler
before people starting ricing it…), and in fact has AWD standard on their
vehilces. And of course, America also has its own AWD family sedan in
the new ‘05 Ford 500. That is by no means a complete list; Many people
cannot tell you what the differenceis between AWD systems and 4WD
systems and use the terms synonymously. This is incorrect, and
if you do it - stop.

Without
getting into the varying complexities of different AWD systems, AWD
basically drives you in a mix of FWD/RWD until you start slipping, in
which case it
compensates by transferring power to the other wheels. The power can
be weighted to either the front or the back, which is unlike 4WD (read
on). For general and inclement weather driving purposes, AWD is more
than sufficient, and after having driven
an AWD Ford Explorer, it is about as immaculate a drive as you can
get in the snow. Of course, there is always a cost, and that
means that you can end up with stuffy engine compartments again and
problems associated with powering and steering the front tires at
the same time. However, if you live in an area with less than adequate
snow plows, a good AWD system will get you by without much
hesistation.

Four Wheel Drive (4WD)

Four wheel drive (4WD) is almost exclusively reserved for trucks or
Jeeps. 4WD vehicles most commonly operate in RWD as opposed to FWD in
AWD vehicles. Have I reached alphabet soup status yet? With modern 4WD
systems you need not manually lock the hubs, all you need is to flip a
switch in the cab. 4WD, as opposed to AWD, does not monitor slippage -
instead you have all 4 wheels turning under power all the time. This
is a rarely needed feature on the road, but can nonetheless be
powerful if you ever have to pull a car out of a snow bank. In other
towing capacities it can be useful but may actually reduce the amount
of weight you can pull. Most people don’t need 4WD and are better
served with AWD, but if you drive a truck it’s probably your best
option for bad winter days.

Personal Reflection

Rear wheel drive is the reigning champion of “fun” driving. When I
take the Mustang out, feeling the power push me is a much better and
balanced feeling. Plus, when I want to I can fish it out a bit in some
sort of cockamamie Steve McQueen impression. Of course, this type of
behavior is best saved for sunny days, and snow requires the most
drastic alteration of driving style.

Front wheel drive is just boring
to me. It does nothing to excite the driver, and feeling your head go
back and rear end sink under power just isn’t as appealing as the rear
wheel drive experience. I don’t feel as though AWD is necessary for my
driving style in the winter (I’m accustomed to RWD) but man was it
nice to be less careful, and anything that raises the margin of error
for the other guy is a good thing. It’s a little more
exciting to drive AWD than FWD because if you want to induce slippage
(this seems like a recurring theme for me) you know the car will
respond before you hit a bank. I find 4WD exhilarating more for the
capability. Just knowing that it will handle off-road
conditions is an awesome. I’ve used it to plow through snowbanks which
is damn fun. When the time comes for you to choose a powertrain
layout, you should take into account the kind of weather conditions
your bound to see and your driving style. Your car can be an extention
of yourself, and the better it matches you the more fun you’ll have
driving it.