How to choose the chassis for your truck ? 

You wouldn’t take a sports car off-road, and you definitely wouldn’t try to enter a rally with a people mover. Certain considerations must be made when choosing a suitable “base chassis” to build a truck that meets your needs. You will already know what you need to transport and where you want to move it to, but have you thought about the underpinnings?

The options for chassis design are wide and varied, taking into account chassis strength, engine power and tyre size. All of these chassis considerations have a bearing on the truck’s ability to do the job efficiently, and ultimately make your business money.

The long and the short of it

The chassis frame is the backbone of the whole vehicle. Manufacturers design a chassis not only for the weight it can carry but also to suit the application it will be used for and the expected road conditions. For example, a shorter wheelbase chassis will often be designed for extreme applications like garbage removal, landscape tipping and concrete mixing where the vehicle might be operating in severe off-road conditions. In this case the chassis will have higher strength properties to suit the application. A longer wheelbase chassis is primarily used for distribution type applications where the chassis needs to be more flexible. This is required in situations like travelling up a driveway where the front of the vehicle can be on a completely different road angle to the rear. A long wheelbase chassis also needs to be able to resist the bending forces of up to a 9-metre long load.

Failing to use the right chassis design for the application can result in premature failure. You also need to ensure you keep within the manufacturer’s maximum Gross Vehicle Mass (GVM) or Gross Combination Mass (GCM) to comply with legal obligations and ensure guaranteed durability.

Don’t go on a power trip

Performance requirements will be specific to your application and should of course be considered when selecting a chassis. Don’t just look at the engine power; consider the whole powertrain including engine, transmission and differential. The combination of all these components gives you the final tractive effort put to the ground to move your load efficiently. In other words, don’t just pick the chassis with the highest power because the gear ratios or transmission type may not provide suitable driveability for your particular needs. Additionally, if not correctly specified, more power can equal more fuel consumption.

Consider the boots

Wheels and tyres can also be a deciding factor when it comes to chassis choice. You may require a small wheel and tyre for a low chassis height suited to hand loading or a larger tyre to achieve a higher ground clearance for off-highway operation. A larger tyre usually means a higher load rating, resulting in the ability to carry larger payloads and accommodate loads with varied centres of gravity.

Make sure you consider the above factors when selecting a chassis. Whether you are a small landscaping company where a short wheel-based tipper will do the job or a long-haul transport business where the truck will see flat, open highway for the majority of its working life, the chassis forms the base of your truck. Choose wisely and consult a professional as part of your selection process.