increase braking distances. check tyre pressures when tyres are cold, ideally
before ... If necessary, issue drivers with tyre pressure gauges and appropriate ...
In a trial performed at the Millbrook track in Bedfordshireiv, two identical Volvo
Fh12.
A Guide to
Tyres This guide shows you how to gain fuel usage reductions of up to 5% by selecting and maintaining tyres and tyre pressure.
VER01 TRAN T_0409
Introduction Taking care of tyres during everyday use and proper selection of correct tyre type are two ways to reduce fuel and running costs – delivering reductions in fuel usage of up to 5%, with longer tyre life. In this guide are day to day operational checks and the factors to consider when buying tyres.
SUMMARY 38% of vehicles driven in the EU have under-inflated tyresii.
We usually forget about our tyres until we get a puncture!
Under-inflated tyres are dangerous, and can increase fuel
If your tyre pressures are 25% too low, rolling resistance increases
consumption by 0.4% per 1 PSI under-inflated.
by 10% and your fuel consumption by 2%i.
Choose Energy Efficient tyres to reduce rolling resistance, fuel consumption by 3%.
checklist Walk around your vehicle before every journey and check
Every 12 months for cars and small vans, and as often as
your tyres.
possible for commercial vehicles, check your wheel alignments. This will increase tyre life, reduce wear and tear on vehicle components, it will also decrease fuel consumption and reduce driver tiredness as the vehicle will be easier to drive.
NB: as tyres age, check thread depths. A 2005 survey by ITIAiii
Think – about vehicle load. Two different tyre pressures are
showed 1 in 8 cars checked on Irish roads were below the legal
usually recommended, one for when your vehicle has no load
limit of 1.6mm.
and/or driving at normal speeds and one for driving with a full load and/or mainly at high speeds. Your instruction manual will have these readings and they are often on a label on the door Don’t forget – ensure your used tyres are disposed of correctly
At least once a week check tyre pressures and condition.
and legally see www.itia.ie and www.tracsireland.ie
Low tyre pressures will affect how your vehicle handles and increase braking distances. Check tyre pressures when tyres are cold, ideally before driving or after you have driven no more than 3km. If necessary, issue drivers with tyre pressure gauges and appropriate training.
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tyre choice Most suppliers of car, truck and bus tyres offer energy efficient, or low rolling resistance tyres, often at a higher cost, but with longer tyre life. Low rolling resistance tyres typically deliver longer life (up to 50% more in some cases) and reduced fuel usage of up to 3%. When comparing tyres use whole life costs and include fuel savings. Choose the right energy efficient tyre. Tyres vary in design depending on where they are going to be fitted on a vehicle. You can buy tyres for the vehicle’s steer axle, drive axle or trailer axle. To get the maximum energy efficiency, they must be in the right place. Specify your tyre preferences when ordering a new vehicle: correct tyre selection is crucial for safety and for operating costs. NB Incorrect tyre diameter can affect odometer and tachograph readings.
energy efficient tyre test results Actual savings on the road are usually about half those on a test track.
This can be as simple as keeping a note of which tyre is fitted on
It’s worth testing tyres that are used in every area of your business to
similar vehicles.
evaluate them against duty cycle and to show evidence of savings. commercial vehicles In a trial performed at the Millbrook track in Bedfordshireiv, two identical Volvo FH12
Fuel consumption improved by 7.6% in one
tractor units pulling two identical tri-axle semi-trailers and both vehicles were loaded
vehicle and 5.2% in the other, when using energy
to 37.7 tonne. Both vehicles were driven for one hour at a constant 50mph (80 kph) with
efficient tyres.
standard tyres and then with energy efficient tyres. In a trial held at the three-mile MIRA (www.mira.co.uk) test track in Warwickshirev,
Fuel consumption improved with the energy efficient
two identical Volvo FL320 tractor units, pulling identical tri-axle curtain-sided semi-trailers,
tyres by 7% for one vehicle and by 7.6% for the other.
were loaded to 38 tonne. The vehicles drove for 15 laps of the track (five laps each at 37mph (60 kph), 50 mph (80 kph) and 56mph (90 kph) first with standard and then energy efficient tyres. In another trial at the MIRA track1, a Volvo FM320 tractor unit coupled to a tri-axle box
The vehicle’s fuel consumption was 9.09 mpg
trailer, was loaded to 30 tonne. This vehicle drove for 15 laps (again, five laps each at
(31.07L/100km) with standard tyres and 9.82 mpg
37 mph (60 kph), 50 mph (80 kph) and 56 mph (90 kph)).
(28.77L/100km) with energy efficient tyres (8% saving).
cars and light vans In tests conducted by TÜV SÜD Automotive (an independent German test agency) in April and May 2008 showed Michelin Energy Saver to offer and the biggest fuel savings and improved brakingvi. The Michelin Energy Saver tyre reduced fuel consumption by 0.2 l/100 km, thanks to
At 6L/100Km, an extra 0.2L savings is 3% in fuel
lower rolling resistance, which is nearly 20% lower than that of its direct competitors and
efficiency. Estimated cash savings of €125 over life
was the most fuel-efficient tyre of those tested.
of the tyre.
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GLOSSARY ENTRIES Rolling resistance: The resistance that exists when a tyre rolls on a
Duty cycle: a description of vehicle operation day to day e.g. ‘trunking’
flat surface.
equates to driving long distances mainly on main roads, ‘multi-drop’ to city deliveries with frequent short stops.
Energy efficient tyres: Tyres that reduce rolling resistance through their design. Reduced rolling resistance means less fuel is needed to move a vehicle forward.
i
Ecodriven project – www.ecodrive.org
vi TUV SUD testing: The braking tests were carried out by the German
ii
Bridgestone 2007 survey of 38,867 vehicles in 19 countries
organisation using three different tire sizes among those most widely
iii
ITIA – Irish Tyre Industry Association – www.itia.ie
sold in Europe, which it purchased in tyre outlets. The comparative tests
iv, 4, 5 ‘Save Fuel with Lower Rolling Resistance Tyres’,
demonstrated that in challenging road conditions, such as on wet surfaces,
Department for Transport (UK), 2006
the Michelin Energy Saver brakes in shorter or comparable distances than six of its main, major-brand competitors (when slowing from 80 km/h to 20 km/h).
checklist Correct specification, e.g. diameter, profile and speed rating for
Location/accessibility of type valves: they must be easy to
vehicle (check manual).
access for frequent checks. Energy saving: ask for fuel efficiency test data from suppliers.
Life of tyre, the longer it lasts the better your return on investment, differences of over 50% have been reported under SEI’s Advice and Mentoring scheme.
For commercial vehicles, discuss potential for re-grooving and re-threading to extend tyre life.
For more information refer to SEI’s other Transport Energy Guides, visit www.sei.ie/business
Glasnevin, Dublin 9, Ireland Glas Naíon, Baile Átha Cliath 9, Eireann
T. +353 1 808 2100 F. +353 1 837 2848
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[email protected] www.sei.ie
