TIM is an acronym for Tire Inflation Maintenance, or, simply put, keeping your tires properly inflated. While TIM probably doesn't seem like an issue of great importance, it truly is, and to a staggering degree.

Why it Matters:
Underinflated tires wear out faster, fail much more frequently and have a detrimental impact on a vehicle's fuel economy.

Under inflated tires wear much faster than properly inflated ones because low air pressure distorts a tire's shape and the way it contacts the pavement, typically grinding the tread off of the sides of the tire’s treaded contact area. Running your tires at a pressure that is just 10% below their preferred pressure setting, typically just 3 - 4 psi, can diminish their usable life by 25%. This distortion also increases "rolling resistance," the culprit behind the devastating effect low tire inflation can have on a vehicle’s fuel economy. Essentially, it takes more energy to propel a vehicle with under inflated tires. If you have ever ridden a bicycle or had the misfortune of pushing a car with under inflated tires, you get it, it takes more energy to propel a vehicle with tires that are low on pressure. Potentially a lot more, as studies show that underinflated tires can diminish fuel economy by up to 10%.

Under inflation is also the leading cause of tire failures. According to government statistics, 90 percent of all tire failures are a result of under inflation, primarily due to the buildup of internal heat under inflation generates. Underinflated tires over heat because they can't maintain their proper shape, becoming flatter than intended while in contact with the road. Tires that are underinflated by just a few pounds can suffer from a weakening of their internal structure and quickly fail.

How Tires Lose Air:
All tires lose air pressure from "permeation," the normal process by which pressurized air migrates through a tire's carcass. While permeation rates vary, almost all tires lose 1- 2 psi every month.

Changes in ambient temperature also cause tire pressures to fluctuate. Air, like all compressed gases, expands and contracts with changes in temperature. While permeation usually counteracts any increase in tire pressure that could be experienced from rising ambient temperatures in the summer months, when the temperature starts to drop in cooler months, tire pressures drop with it. Tires will typically lose 2% of their inflation value for every 10 degrees the temperature drops. In addition to the unavoidable effects of permeation and mother nature, tires also lose pressure from slight leaks around the tire bead, porous wheels, loose or leaky valves or slight punctures. No matter how new your vehicle or tires are and despite your best efforts, your tires WILL lose pressure and should be checked and "topped-off" every month.

Why Now?
TIM concerns are not new. For years, every vehicle manufacturer, tire manufacturer and the US government have been telling us to correct our tire pressure at least every 30 days. Take a look in the owner's manual for your car or truck. No matter what you are driving, if it was made in the last 20 or so years, the owner's manual will instruct you to check your tire pressure every month. We all know we should do it, yet, according to AAA, less than 15% of us do.

In the past Tire Inflation Maintenance was largely ignored by most motorists. Until this decade almost all vehicles required oil changes or other maintenance services every three months or 3,000 miles, whichever came first. All competent service facilities check a vehicle's tire inflation every time they perform an oil change or maintenance service. With no particular sense of urgency surrounding tire inflation, most consumers, if they thought about it at all, figured these routine services were enough to maintain their tire pressure. Recent advancements in engine technology, as well as overall quality improvements, have permitted vehicle manufacturers to extend the duration between required vehicle maintenance intervals. Some vehicles now only require an oil change, or any scheduled service, once a year. In other words, we are seeing our mechanics less, so the burden of maintaining our tire inflation has shifted to us, the motoring public.

Constantly rising oil, fuel and tire prices have also added to the recent popularity of TIM, as nothing you can do to or for your vehicle will save you more than simply maintaining your tire pressure. Further, we care more. Society in general is realizing that we need to take care of our planet if we expect it to take care of us, and TIM will help you do your part.

What Can I Do?
Top-off your tires every month. As a member of the TIM Auto Club, it's fast and it's free. Your TIM Dealer will even remind you when to do it and reward you for participating with a FREE membership. But please, participate. If you miss a month, come the next month, it's that important.