If you follow trends in the automotive industry, you may have noticed that manufacturers are putting more focus on four-wheel-drive as opposed to two. They are eliminating some of their conventional saloon cars and bringing a number of new SUV's to the marketplace, to tempt the Australian consumer. You may be thinking about buying one of these vehicles for the first time but should know that they are somewhat more complex than your old car. In particular, you need to pay more attention to the transmission, so what do you need to be on the lookout for?
The Way to Go
Four-wheel-drive vehicles are intended to be very stable in unpredictable conditions. This means that they will be surefooted when those rainstorms descend and will help you maintain control in an urban jungle as well as out in the "bush." To do this, both front and rear axles work in tandem and automatically adjust the level of traction due to a complex array of sensors and gears. In other words, there's a lot more "going on" beneath you, when you drive one of these four-wheelers.
To start with, there are two independent differentials, one at the rear and one at the front. In between these units is a transfer case, which helps to distribute power selectively to the front or the rear, depending on the conditions.
These three units have special fluid within and these need to be monitored and topped up, as needed. Usually, the fluid in the differential is different to the fluid in the case, and they do not intermingle.
Seals and Motor
You will also need to keep an eye on the seals that separate the differentials from the transfer case, or they will degrade. The motor that powers the transfer case is another area for your attention, to ensure that all the electrical connectors and valves are in good condition and doing their job.
Looking at the Hubs
The axle on this type of vehicle has another component that is not found on a two-wheel drive counterpart – the locking hub. This is a complicated network of gears that are meant to connect and disconnect one axle at a time, should it not be needed. This allows you to drive in two-wheel mode only in normal conditions on a paved road, which will help you save money on tyre wear and fuel consumption. However, these hubs do require regular maintenance to ensure that they keep working as they should, and it's another area for you to monitor.
Once you buy your four-wheel-drive vehicle, ensure that you take it in for a regular inspection and keep an eye on those fluid levels in between. For more information, contact your local mechanical repairs shop.