If you've recently taken ownership of a vehicle with a four-wheel-drive transmission for the first time, you may be getting used to its idiosyncrasies and learning more about the way it works. You may realise that it is significantly different to your previous, two-wheel-drive vehicle and want to get the most out of your ownership by looking after the vehicle correctly. However, you may have questions when it comes to the way that the engine distributes its power and how it's possible to turn all four wheels at once. This is the job of the transfer case, a component specific to the world of all wheel drive. What do you need to know?
How Transfer Works
Four-wheel-drive vehicles are known for their efficiency and safety on the roads and this is due in large part to the fact that all four of the wheels are providing traction. In slippery conditions this can make a significant difference, as two wheel drive vehicles may be struggling to adhere to the road. However, your vehicle only has one engine and therefore one source of power and without the transfer case, it would be impossible to deliver traction to both front and rear axles.
This component sits between the gearbox and the rear axle, usually around the centre of the car. Within it, there can be a number of different gears or chains that take the power from the engine and "split" it towards the front or rear axles. Two different shafts will emerge from the transfer case and one will go towards the rear axle, while one will return to the front.
Different Types of Case
The most sophisticated transfer cases are able to vary the amount of power that is transmitted to either axle according to the road conditions that are being encountered. The case will also contain a set of low gears that are designed to drive the car through very demanding terrain, as you may find in an off-road situation.
Some vehicles are equipped with a very simple transfer case if they are designed to be in four-wheel-drive mode at all times. However, most SUVs and trucks designed for the domestic Australian market have optional four-wheel-drive, or various different modes and as such the transfer case is much more complex inside.
Looking after It
As you can imagine, this component has to endure a lot of wear and tear and needs to be carefully serviced according to manufacturer recommended intervals. Check your vehicle in now for its first service, so that you don't overlook this crucial part of vehicle ownership.