HOW AWD, RWD & FWD CARS ACTUALLY WORK

Sanuj Raj
5 min readMar 20, 2021

AWD, RWD & FWD

A car is generally a dense amount of engineering that is done and perfected over the course of the 20th century and still, we are not there. It's a good thing as we know that nothing is perfect, which applies to cars as well. Although today’s cars are more reliable, safer, and faster than ever before.

The limiting factor in high-performance cars is the tires and not the engine, as to how faster a car can go.
Take the Bugatti Chiron for example, its tire manufacturer Michelin guarantees the safety of its tires up to 270 mph but one of the versions of the car has recently achieved upwards of 300 mph.

The only part that is in direct contact with the road is the tires. The power generated by the engine is transferred through gears to the differential and from the differential to the tires. Over the course of several decades, engineers have found out many methods on how to transfer the power to the tires.

History:-

First, in the very beginning, they choose RWD and that too not all the rear wheels were driven only one wheel was chosen for the power transfer because of differential issues. Later on, a solution in the form of differential itself was devised and both the wheels were now powered. FWD was developed in the 50s and 60s.
AWD was the last one to be invented, it was born in the rally world. As a matter of fact, Audi was the one who used AWD as a Quattro system for the first time. As a result, Quattro was untouchable in the rally world. It made it a dangerous competitor.

How to Configure Tires?

The format of writing the configuration of tires is as follows- the are 2 numbers separated by a * symbol, the first number represents the number of tires in the vehicle and the second number represents the working wheels. If an SUV is a brand as 4*4 then it means it has 4 wheels and all 4 wheels are working wheels and are attached to the engine. Similarly, this number will be different for trucks and other vehicles.

If you’ve ever paid notice to a tire, there are many writings on it, one of them represents the dimensions of the tire. For example, 215/60R17 means 215 mm is the actual contact section, 60 is the percentage of the height of the tire sidewall wrt width of the actual contact section, R means it’s a Radial tire and 17 is the diameter of the tire's inner rim.

AWD (All Wheel Drive)

AWD is the best mode of transfer of power to the wheel. It is the optimum use of car real estate to push the car forward. AWD cars generally expensive and their height is greater than non-AWD cars. In this, the transfer of the car’s power is done through all the wheels. The front wheels are directly connected without a connecting shaft and the rear wheel is connected by a transfer shaft and with a differential.

A Complete in-depth Review of AWD and 4WD

Performance-Wise

Generally, AWD has the best traction in drag races when you need to start from a standstill. Although this is not a real-world situation this obviously helps when you are in desperate need of traction at low speeds.
The AWD lacks overall acceleration at the highway speeds because the torque is split 4 ways thus reaching a small portion to each of the wheels.

What is the actual difference between FWD and 4WD?
AWD is powering all the wheels at all times regardless of the condition and traction whereas the 4-wheel system allows for powering the one set of wheels at any particular time, all-wheel are powered only when there is a need for traction.
Frequently, manufacturers try to manipulate people through false advertising. So next time be wise and know the difference.

For more information on the difference visit the link: https://www.edmunds.com/car-buying/awd-vs-4wd-whats-the-difference-and-which-to-choose.html

RWD (Rear Wheel Drive)

Rear Wheels becoming increasingly popular these days. The market is shifting towards SUVs and RWD sits at the forefront of the revolution. Popular manufacturers like Lamborghini, Ferrari, and Aston Martin are all coming up with their first-ever SUVs.

Performance-Wise

RWD is for the real world, it performs well in the instant acceleration situation when to need to overtake someone, the rear driving wheels provide the car with the maximum acceleration possible due to the shifting of the weight of the car to the rear during acceleration.

And in off-road situations, RWD comes into play, as the above-mentioned factors come into play and help the car get to anywhere without worrying.

What is Ladder on Frame Chassie?

These types of vehicles are basically scaled-down smaller trucks that are shaped in the form of cars. Mostly macho SUVs fall into this category. A full-fledged ladder runs down the vertical length of the vehicle supporting the body of the vehicle, giving extra strength. Generally, these kinds of bodies are higher than usual and are tall cars. These can be FWD, RWD, or even AWD.

What is a Monocoque Chassis?

These are smaller cars that are mostly FWDs. This kind of chassis was developed to be passenger vehicles from the ground up as both frame and chassis are one single piece. Hatchbacks, Sedans, and even some compact SUVs fall into this category. This type of chassis is safer than a ladder-on-frame design.

FWD (Front Wheel Drive)

FWD is becoming a thing of the as the market is shifting towards SUVs but from the past, we can see that the FWDs were cheap to construct so they are generally able to be sold cheaply. Small hatchbacks fall into this category, but nowadays many SUVs are coming with FWDs.

Performance-Wise

The FWD construction doesn’t provide much acceleration as the majority of weight shifts to the rear wheels during acceleration and the front wheels are left underweight. Smaller cars generally don’t need much performance so they are given FWDs which makes them affordable. During the start of the car industry, vehicles came with RWD construction but as soon as FWDs were invented in the late 50s, the market became flooded with FWDs due to their more advantageous nature.

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