Benefits of Rear Wheel Drive Cars
benefit to rear wheel drive is that it spreads the loads of
the car across all four tires of a car. In a rear
wheel drive car the rear wheels do the pushing while the front
wheels are reserved for the steering duties. In front wheel
drive cars the front tires must perform both functions. Each
front tire in a front wheel drive car must do two tasks. Both
the cornering forces and the engine acceleration/deceleration
forces in a front drive car act on the same tire.
So in a front drive the tires capacity can be
easily exceeded. In a rear drive car the rear tires
handle the engine acceleration/deceleration while the front only
need to handle the steering forces. Not only does this balance
the load on the tires but it reserves the front tires
exclusively for the all important steering duties.
Other Benefits to Rear Wheel Drive.
O.K., some assumptions : All comparisons are of
equal weight cars without traction control. Braking comparisons
assume maximizing the ability (two feet on the pedal pressing as
hard as possible) of a perfectly working four channel anti-lock
- Better weight balance. Most rear wheel drive cars have
the engine in the front and the drive components in the rear.
Front drive cars have everything up front. By properly balancing
the front and rear of the car you can improve the handling,
acceleration, braking, and thus safety of a car.
- Better acceleration. On all but the slipperiest
surfaces rear wheel drive cars accelerate faster than a front
drive car from a stop. This is because when you accelerate
quickly from a stop the weight of the car transfers to the rear
of the car. In a rear drive car this places extra weight on the
rear of the car, essentially jamming the tires into the road
greatly increasing traction. In a front drive car, when the
weight goes to the rear, weight is taken off of the front
wheels. This allows the front wheels lose traction and spin
easier. If the wheels are spinning not only does this slow you
down but it also makes it difficult to steer the car. In the
rear drive car the front tires are available for steering even
if the rears have lost traction.
- Better Road Holding. The better weight balance of rear
wheel drive allows the car to handle better. The more even
weight allows the car to drive neutrally through a corner. This
means both the front and rear of the car have near equal loads
acting upon them. In a front drive car the the heavy front end
causes the front end to have a higher load on it. This will
cause the front tires to eventually lose grip well before the
rear tires are fully loaded. Front tires on front drive cars do
much more work than the rears causing them to wear out much
faster. It is best to balance the load as best you can among the
four tires. If you are accelerating or slowing down (engine
braking) these forces will act upon the already heavily loaded
front tires of a front drive car. In a rear drive car the front
tires are left for steering even when accelerating or engine
braking. Sharing the work among all four tires is the key.
- Better Stopping. Because of the better balance rear
drive cars brake better. When you stop a front drive car the
excess weight in the front of the car allows the force on the
front tires to exceed the limits of the tires. The relatively
low weight on the rear of a front drive car does not allow the
tires to be used to their maximum ability. When panic stopping
weight will transfer to the front in both rear and front drive
cars but there is more weight left for rear braking action in
the rear drive car.
- No Torque Steer. Front wheel Drive cars have a problem
known as Torque Steer. This occurs when the acceleration of the
engine effects the cars steering. Since the driveline is
connected to the steering wheels the torque of the engine
applies force to the front wheels causing the car to pull to the
right during acceleration. Rear Drive cars do not have this
problem since the engine is not connected to the steering gear.
- Better Ride and Feel. The light front end of the car
allows it to "turn in" to a corner easier. The car feels more
nimble and controllable. Since the front is not so heavy it is
not burdened by needing strong springs to keep it under control.
This allows the suspension to be set up softer while maintaining
good control ability. The absence of drive shafts (half shafts)
and CV joints in the front of the car allows the front
suspension to be designed for maximum steering efficiency. The
lower rotating weight of the front wheel assemblies improves
steering response and ultimate grip. Granted that a rear drive
car has more weight at the rear but it can be handled by the
underutilized (compared to the front tires in a front driver)
- Better Serviceability / More Rugged. Ever notice that
cops and taxis avoid front wheel drive like the plague? That is
because rear wheel drive cars are more rugged and easier and
cheaper to fix.
- Better Ultimate Ability.. Purpose built race cars are
almost always rear wheel drive. In production based racing
series front wheel drive cars are given a performance advantage
to make them equal to rear drive cars. Usually this is in the
form of a weight break. Granted we shouldn't be driving our cars
like race cars on the street but in an emergency having the
extra ability in the car is an advantage I would like to have.
So why do automakers use front drive cars?
Well I guess there are a couple of good reasons I can think of.
Anybody else have any more? If so e-mail
me and let me know.
- Traction in Snow and Ice. When not under hard
acceleration front drive cars have more weight over the front
wheels. This gives more traction for acceleration in very
slippery conditions. This is the biggest perceived advantage to
a front drive car. However, today's rear wheel drive cars with
traction control and independent suspension do very good in the
snow. But for areas of the country that have extreme amounts of
winter weather this may be enough to justify a front wheel drive
- Packaging. In front drive cars the engine and
drivetrain can be pre-assembled as one unit and then popped in
to the car during assembly. This probably leads to a more
efficient assembly operation.
- Cost. Due to easier manufacturing and a few less
components it may be cheaper to manufacture a FWD car.
- Passenger/Trunk Space. Since you do not need to run a
driveshaft down the middle of the car you may be able to get
more interior room. Funny that front drive cars have a hump down
the middle anyway! Not having a rear drive suspension can allow
the trunk area to be larger.
- Demand. Until we tell the automakers we want rear
drive cars they won't build them. So let's tell them!