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Your choice of vehicle impacts your business. The right choice can improve your fuel efficiency, safety and profitability. This guide contains advice on the features you need to consider when purchasing your next vehicle.

The five-step selection process

1. Operating environment and vehicle layout

Ask...

 Vehicle dimensions

2. Vehicle performance

Next, consider factors that affect performance, such as engineering and vehicle components. Some of these are subject to legal requirements. See the vehicle standards you have to meet.

As a foundation, your vehicle needs sufficient power to handle the workload, using the least amount of fuel and at the lowest life cycle costs. Consider:

  • engine power

  • torque requirements

  • transmission gearing

  • differential ratios

  • wheels and tyres.

Also consider investment in new braking technology (external link)

Fuel efficiency

You can reduce your fuel costs by:

  • carefully matching the engine size to the workload demand. Every additional 5hp can increase fuel consumption by 2%

  • fitting aerodynamic cab deflectors to help reduce aerodynamic drag and inter-vehicle spacing. These can improve fuel efficiency from at least 6% to more than 20%, depending on the body and the load

  • using road speed limiters or cruise control features, which can save up to 6% if set correctly

  • using semi-automatic and fully-automatic transmissions which now use the same or less fuel than manual transmissions.

Performance checkpoints

  • An engine geared to run at 1450rpm at 100km/h uses approximately 4% less fuel than one geared to run at 1600rpm at the same speed.

  • Idling can add 20 to 30% to engine hours.

  • A fixed drive fan can use 10% of the engine power if it operates all the time, but may only be required for 2–5% of the time. Consider fitting electrically-driven thermostatically-controlled fans. Determine whether it is necessary for the fans to turn on automatically when the air conditioning system turns on.

  • At highway speeds, over half the energy required goes into overcoming aerodynamic drag. Reducing aerodynamic drag by 25% will reduce highway fuel consumption by 10–15%. Reductions in aerodynamic drag of up to 50% are achievable. However, the power-train still needs to receive sufficient cooling.

  • Dead insects behind the front windshield indicate an airflow problem.

3. Health and safety

Ensure your chosen vehicle meets all legal requirements under the applicable transport regulations, the Land Transport Rules and the Health and Safety in Employment Act (external link)  (HSE).

Other things you need to consider:

  • Features that affect the normal driving of the vehicle or its driveability – the vehicle's handling, the effectiveness of the lights and cab layout.

  • In-service reliability, to reduce risk of a failure that could cause a crash.

  • Active safety features that help avoid a crash occurring – ABS, traction control and road speed limiters.

  • Passive safety features that protect the driver and other road users when a severe crash is unavoidable – safety belts, under-run protection and crashworthy cabs.

  • Driver occupational safety and health issues such as safe access into the cab, the quality of the driver's seat, cab noise, the fitting of tail lifts and other devices.

  • Features that increase the vehicle's visibility – for example daytime running lamps, conspicuity tape.

  • Features that reduce noise and emissions.

  • Anti-lock braking system (ABS), electronic brake stabilisation (EBS) and other brake technologies can significantly improve brake performance.

  • Many trucks now comply with the European ECE 29 cab strength requirements, providing added protection in head-on crashes and rolls.

  • Under-run protection saves lives. Some trucks are now factory-fitted with front, side and rear under-run protection.

  • The Health and Safety in Employment Act (external link)  (HSE) recognises the cab as the driver's place of work, placing greater consideration on health and safety.

Safety checkpoints

4. Maintenance

Maintenance typically makes up 5–10% of operating costs and increases as the vehicle ages or when operated in hard conditions. Choosing the right vehicle and regular maintenance will save your business more expensive downstream repairs and the cost of delayed delivery to your clients.

Ask other operators if the vehicle you're considering is reliable. Consider features that improve reliability – the use of synthetic lubricants in axles and transmissions and sealed-for-life bearings.

Maintenance checkpoints

  • The amount of fuel consumed is a better indicator of engine wear and when to service your vehicle than distance travelled.

  • Synthetic lubricants outperform mineral lubricants at all temperatures. They can reduce fuel consumption by up to 0.5% in summer and 2% in winter.

  • A 15psi under-inflation of tyres will increase rolling resistance by 6%.

  • Keeping tyres inflated to the manufacturer's recommendations decreases the likelihood of tyre blowouts and flats.

5. Appearance

Vehicle appearance can contribute to attracting business and retaining drivers.

Consider:

  • cab layouts that enhance driver comfort

  • vehicle styles that appeal to your clients (aggressive looking vehicles may detract)

  • livery that enhances your company image and inspires pride in your drivers.

Checklist for vehicle specification

Use this checklist to work out the specifications for your next vehicle.

Operating environment and vehicle layout

Estimated total kilometres that will be travelled each year

      

Types of load to be carried

 

Location at which vehicle will be based (main depot or secondary depot?)

 

Accessibility to loading/unloading areas

 

Number of drivers who will regularly use the vehicle

 

One-way or return trips?

 

Expected maximum and average payload

 

Average daily utilisation of the vehicle

 

Average daily load factor

 

Will vehicle be operating on hilly terrain, off-highway, in congestion, etc?

 

Will vehicle be required to operate any additional equipment (eg Hiab)?

 

Will vehicle be required to tow a trailer?

 

Will vehicle stay on the same work for all its operational life?

 

Will vehicle be required to comply with any specific industry sector requirements (eg tankers)?

 

Type of body required to carry the load

 

Load securing arrangements

 

What is the best configuration for the intended task?

 

What are the expected dimensions?

 

Are the weight and height limits required to comply with SRT workable?

 

Is the tare mass as low as is practical?

 

What are the expected axle loadings?

 

What will the GVM and GCM be?

 

How will the configuration affect road user charges for that vehicle?

 

What types of specifications have worked best in previous operations?

 

Vehicle performance

Is the area at which vehicle is based hilly or flat (startability)?

     

How steep are the hills that the vehicle is likely to have to negotiate (gradeability)?

 

Is the vehicle likely to be operated off-road?

 

What is the main type of road surface the vehicle will be operating on?

 

What are the temperature extremes?

 

What are the prevailing winds?

 

Engine option – eg fully electronic (fly by wire)

 

Transmission type (synchromesh, constant mesh, non-synchromesh, automatic, automated)

 

Final drive ratio

 

Exhaust (the greater the back-pressure, the greater the amount of fuel used)

 

Cooling fan (specify the smallest variable speed fan necessary for requirements)

 

Fuel tank size (carrying excessive amounts of fuel reduces payload capacity and increases running costs)

 

Radiator shutters

 

Auxiliary braking (engine brake retarder – what type?)

 

Type of brakes (ABS, EBS or conventional; drum vs disc)

 

Running auxiliary equipment when vehicle stationary

 

Speed limiting

 

On-board vehicle monitoring

 

Will cruise control be an advantage?

 

Type of suspension (air or leaf springs?)

 

Type of tyre (super single or dual?)

 

Tyre tread pattern

 

Central tyre pressure monitoring

 

Set back or conventionally mounted front axle?

 

Conventional or low maintenance hubs and bearings?

 

Type of cab (full sleeper, day cab, extended cab? COE vs conventional?)

 

'Dress up' equipment that improves return on investment

 

Air conditioning

 

Type of seating

 

Will existing drivers need retraining?

 

Health and safety

Brake system, including ABS, EBS, discs vs drums etc

      

Under-run protection (sides, rear and front)

 

Safety belts

 

Conspicuity

 

Cab strength under impact (to the ECE 29 standard)

 

Do the mirrors provide good side and rear visibility? Should the mirrors be heated?

 

Driver access to the cab

 

Seat adjustment

 

Driver comfort

 

Cab layout

 

Storage space in the cab

 

Load securing provisions

 

Lifting equipment such as tail lifts

 

Maintenance

Service intervals

      

Cost of service and parts

 

Lubricants

 

Service support package (if outsourcing maintenance)

 

Sealed-for-life bearings

 

Availability of parts

 

Reliability and expected life of components

 

Compatibility with other vehicles in your fleet

 

Knowledge of staff undertaking the repairs

 

Expected life cycle cost of maintenance

 

Appearance

Styling 

 

Signage

 

Driver preference

 

Brand promotion

 

Client requirements

 

Overall image

 

Calculating axle weights

Use the axle weights calculator to the calculate axle weights of your vehicle under various loading conditions.

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