Although, we don't think about it often, all of a typical vehicle's weight rests on just four contact
points – its tires. Therefore, tires should be checked regularly – at least once a month. Properly
inflated tires increase tire safety, reduce fuel consumption and exhaust emissions. For fleets,
problems arising from poor tire maintenance are compounded because of the number of
vehicles. On the positive side, the benefits increase with proper tire maintenance.
Tires are engineered to perform safely day in and day out. To do this job well, regular
maintenance is required. Most responsible operators of tractor-trailer fleets have put into place
procedures to ensure regular tire inspections, while in the case of private-passenger or service-
type fleets, regular inspections can be overlooked. Again, establishing a firm policy and effective
procedures is the best way to ensure tires on all vehicles are checked regularly.
The tire tread provides the gripping action and traction that prevent the vehicle from slipping or
sliding, especially when the road is wet, icy or snow covered. In general, tires are not safe and
should be replaced when the tread is worn down to 1/16 of an inch. Tires have built-in
treadwear indicators that let you know when it is time to replace your tires. These indicators are
raised sections spaced intermittently in the bottom of the tread grooves. When they appear
"even" with the outside of the tread, it is time to replace your tires.
Tire Labels – Including Treadwear Rating
Treadwear grades are an indication of a tire's relative wear rate. The higher the treadwear
number is, the longer it should take for the tread to wear down. Review the DOT safety standard
code, which includes the date of manufacture, to ensure the tires are in the best condition. For
the meaning of other markings on the standard tire, see below.
November 2010 Page 1 of 2
Proper Tire Inflation
Without good tires that are properly inflated, vehicles will not accelerate, brake or steer properly.
In addition, safety devices such as anti-lock braking systems, traction control systems and
stability control systems may not function correctly. By following a few simple steps, you will
increase your safety and that of fellow drivers and pedestrians. You will also improve on fuel
economy and prolong the life of your tires, helping to save both energy and money, while
reducing your vehicle’s impact on the environment.
The Effect of Tire Condition on Fuel Consumption
This simple chart below indicates the effects that improperly inflated and aligned tires can have
on tire life and fuel costs:
Percentage of Under Inflation Percentage Wear Increase Fuel Use Increase
10% 5% 2%
20% 16% 4%
30% 33% 6%
40% 57% 8%
50% 78% 10%
Become “Tire Smart”
The Government of Canada and the Rubber Association of Canada have developed a website
to help individuals become “Tire Smart.” Visit www.betiresmart.ca
Winter Tire Care
Your tires need special attention during the winter. Cold temperatures decrease the air pressure
in tires. This just adds to the rolling resistance caused by snow and slush. Each tire that is
under-inflated by 2 psi (14 kPa) causes a 1% increase in fuel consumption. So check tire
pressures regularly, especially after a sharp drop in temperature.
Before adding air to your tires, let some air out of each valve and blow some air out of the hose.
This prevents moisture from gathering in the tire valve, where it can freeze and cause the valve
to leak. If possible, use your own tire pressure gauge, since the gauges built into air pumps at
service stations are often inaccurate or missing.
Check tire wear and condition prior to winter season to maximize safety!
Proper tire maintenance is not only critical to the safe operation of your vehicle; it will also:
Improve fuel economy;
Extend tire life;
Provide better vehicle handling;
Help to prevent avoidable breakdowns and collisions;
Reduce exhaust emissions that contribute to environmental, health and climate-
November 2010 Page 2 of 2
Aviva and the Aviva logo are registered trademarks of Aviva plc and used under license by Aviva Canada Inc. for use by its family of
companies. Information provided in this document is for reference only.