How to cut your fuel bill

With the price of diesel unlikely to fall in the near future, this is no time to be frittering away expensive fuel. Commercialmotor.com  brings you some simple ways to make savings. We’ve broken our tips down into three broad categories: specification, day-to-day operation, and purchasing.

Specification

Driver training

The biggest single influence in cutting fuel is the person behind the wheel. Training helps drivers to anticipate better, reduce idling and maintain momentum. Raising standards also makes the job less stressful. Manufacturers quote fuel savings in the region of 10%.

Improve the truck’s aerodynamics

An estimated 60% of fuel used is consumed just dragging a truck through the air. Improve the vehicle’s aerodynamics and you could slash your fuel bill. Obvious places to start are side collars at the rear of the cab, an under bumper air dam, and skirts along the length of the trailer. For the ultimate in truck aerodynamics, check out the Iveco Glider concept vehicle.

In-cab telematics

One long-term problem with driver training is continued monitoring and assessment. All too often drivers return to old habits. Employing telematics, to monitor driver technique and the amount of fuel used, arms transport managers with the right information to do something about it.

Invest in aerodynamic trailers

Few inventions have had a big impact on the road haulage industry like the aerodynamic trailer.  Perhaps the most iconic is Don-Bur’s Teardrop, which achieved a staggering 30.3% fuel saving when compared with a regular tandem-axle trailer. But Don-Bur is not alone: Cartwright has also made a   huge impact with its Cheetah aerodynamic system, and more recently its Cheetah Fastback trailer. Most of the trailer manufacturers are working on their own aerodynamic designs, and the Bevan Group has developed the sloping roofed rigid.

Mind the gap

The larger the gap between the back of the cab and the front of the trailer, the more wind turbulence created, and the worse the vehicle’s aerodynamics. Plus, of course, a more snug gap improves handling.

No clutter

Truck manufacturers spend millions of pounds developing the most fuel-efficient designs, and then we ruin their hard work by sticking bull-bars, spotlights, airhorns and Michelin Men all over the place. The more clutter, the worse the fuel economy.

Run cryo fridges

Cryogenic fridges are not only quieter and more efficient than diesel units, they also consume less energy and don’t require fuel to operate because they use CO2 as a coolant. Thermo King’s CryoTech range provides quicker temperature recovery than a diesel reefer and exceeds the PIEK low-noise standard, which means its maximum operating noise level is just 60dBA – more than 90% quieter than a diesel trailer – and for each cryo unit you’ll also save around 850 gallons of red diesel a year.

Set air deflectors correctly

It’s all very well having an air deflector fitted, but it’s not going to help at all if it’s been set at the wrong height. Although it’s not an exact science, check for dead flies on the top front of the trailer.

Specify the right driveline

Getting the right tool for the job is half the battle. Spec direct-drive transmissions and single-reduction rear axles – hub-reduction and overdrive boxes are bad news.

Steering-trailer axles

When it comes to wheels and tyres, reducing friction is the key to saving fuel, so to have a trailer axle scrubbing its way around tight corners and roundabouts is going to cost you in the long run. Switch to a steered-trailer axle to reduce the drag, saving fuel and tyre wear.

Two pedals are better than three

Automatic transmissions won’t improve the very best drivers on your fleet, but they are likely to increase the standards of the other 90%. Autos eliminate basic driving errors such as over-revving and making too many gear changes.

Use low rolling resistance tyres

All major tyre manufacturers offer a low rolling resistance tyre, and although not cheap, they could save you money in the long run. According to Michelin, its Energy range allows fuel economy savings of up to 6%. Meanwhile, Continental says an operator that fits its Eco-Plus tyres will save in excess of £43,000 a year (based on a fuel price of 117ppl and calculated using a fleet of 30 trucks each averaging 100,000km/year and 8.5mpg (33.2L/100km).

Use synthetic oil

It’s not just tyres that suffer from friction – friction in the engine also affects your fuel economy. It’s therefore important to use the right oils, such as a high-grade synthetic one. Shell says its Rimula 5W/40 can save up to 1.1% in fuel consumption compared to its synthetic 10W/40 oil. Axles and gearboxes also work under friction, so check the manufacturer’s guidelines when servicing and making fluid changes.

Day-to-day operation

• Avoid leaks - Watch out for leaks in the fuel tank and filler neck. A hole in the neck could result in a loss of a litre of fuel a day, costing a few hundred pounds during a year.

• Block-shift - Block-shifting saves fuel and time, and prolongs the life of the clutch. Each gear change costs about 0.1 litres as the driver reintroduces all-out combustion to the engine. Any unnecessary gear change raises the amount of wasted fuel. Driver training by Mercedes-Benz showed reducing the number of gear changes by 20% can improve mpg by 2%.

• Change fuel filters - Regular servicing helps to keep your truck operating at peak efficiency, so make sure that fuel filters are changed regularly.

• Don’t be idle - Trucks that idle are driven by people who are idle. On average, an engine between 11 litres and 14 litres, will use 1.2 litres of diesel on tickover every hour. Driver trainers urge transport managers to monitor idling levels through telematics, with a view to keeping idling time well below 5% in any working week. Some truck manufacturers offer idle shutdown systems.

• Involve the driver - Pick the right scheme and drivers will be more than co-operative. Bonus schemes can work, but can also lead to cheating. Why not develop a league system based on telematics, fuel economy and the number of digi-tach card indiscretions? A points-accumulator scheme can also be used to bring poorer drivers up to scratch.

• Keep those curtain straps taut - The smoother the side of the truck, the better its aerodynamic properties, so always ensure curtain straps and buckles are pulled tight. Better still, go strapless or use a box van instead.

• Let it lug - Today’s torque-based engines often boast more than 2,000Nm as low as 1,000rpm. It wastes fuel not to use this latent power. Premature gear changes force up revs, and with less torque available above 1,400rpm, it’s a waste of fuel. Use the torque and let the engine lug. Truck manufacturers claim a truck can use 15% more fuel by climbing hills using power rather than torque.

• Lift redundant axles - The more points of contact your vehicle has with the road, the more energy you’ll need to counteract the friction created. Energy lost between the tyre and the road accounts for up to 50% of fuel consumption depending on speed, so by lifting axles off the road there are fewer points of contact and less friction, resulting in reduced fuel consumption.

• Listen to the right music - Psychologists at the West London Institute of Higher Education found that drivers listening to loud, repetitive, quick, rebellious music drove in a similar fashion. They used 25% more fuel per journey than drivers listening to gentle, melodic, thoughtful tunes. So swap Rage Against The Machine for Enya.

• Manage your tyres - Always ensure that tyre pressures are correct, because a 10psi fall in pressure will result in a 1% drop in economy. Watch for uneven tyre wear too. This is a sure sign of poor wheel alignment. According to Freight Best Practice, a 1º misalignment on one axle could increase fuel consumption by 5%. And  the more worn a tyre is (although still within legal limits), the lower the rolling resistance, and the better the fuel economy. Dust caps should always be in place, and ideally made of metal rather than plastic, for durability.

• Repair torn curtains - The smoother the surface and the fewer the cavities, the less wind resistance and the more fuel-efficient your vehicle is. With this in mind, always sheet empty tipper bodies. Torn curtains are not  only a security hazard, they will also have a detrimental effect on fuel economy.

• Sheet empty tipper bodies - The smoother the surface and the fewer the cavities, the less wind resistance and the more fuel-efficient your vehicle is. With this in mind, always sheet empty tipper bodies.

• Slow down - Cutting your speed on motorways to 52mph will do two things: first, it will save you upwards of 2% on fuel as the engine isn’t working so hard; and second, the travelling speed will be more constant because you won’t have to keep adjusting your speed when you meet slower traffic, which in itself can cost 5% in fuel.

• Turn off the AC - Everyone knows air conditioning consumes fuel (lowering economy by around 1.5%), but running with the window down is even worse at motorway speeds. For the ultimate fuel saving, keep the window shut and turn off the AC – just don’t forget the deodorant! “However, if you get desperate for air, you can always open the roof hatch an inch,” says DAF demo driver Richard Kingston, “it may even act as a mini spoiler!”

• Use cruise control - Correct use of cruise control allows the engine to work at its optimum level. It is best used when the road is congestion- free, dry and the lay of the land consistent. According to truck manufacturers, cruise control can save up to 10% in fuel consumption on longer journeys. And don’t use the resume button to get back up to speed, because it will burn unnecessary fuel. Instead, work your way back  up gradually and reset cruise when you reach your chosen speed.

Purchasing

Buy double-deckers

No, not the chocolate bar, the trailers. The extra height over a 4m trailer will damage your fuel economy by around 6%, but if the height of your load permits you to double-up you could lower fuel costs per tonne by as much as 15%.

Buy Euro-5

Euro-6 trucks will be heavier, more expensive and will have to rely on EGR, SCR and a particulate trap to get the emissions to the required standard – and they definitely won’t be more fuel-efficient than Euro-5. If you want to keep your fuel bills low, then avoid Euro-6 trucks for as long as possible.

Buy fuel at lower temperatures

Diesel constantly expands and contracts depending on the temperature, and while the difference at the pumps is negligible – and offset by the rate at which the fuel is burnt in relation to the air density – buying fuel in bulk will make a difference. A rise in temperature of 10ºC can mean a change in volume of up to 2%, so it pays to buy when the temperature is low or to negotiate a correction  factor with your supplier.

Use fuel cards

Many of the major fuel suppliers offer a fuel card service that not only lets you pay for your fuel on credit, but also gives you a discounted rate. Shop around for the best price and you could save up to 3ppl.