Is there anything more poetic than the allure of the open road? Scenery flashing by as the endless miles of the highway unfurl before, picturesque villages chanced upon almost by accident, the squeal of rubber and protesting metal as tires that should have been replaced months before lose their grip on a treacherous mountain turn...
Melodrama aside, properly maintained tires can save your life. Although tire rotation as part of a regular preventative maintenance plan can dramatically help to extend tire life, the fact remains that at some point you will have to replace your tires.
There's an old saying that you have to spend money to make money. In the case of maintaining your vehicle, it's really more of a case of spending money to save money. Paradoxical? Perhaps, but it's the truth.
Driving on old, worn tires drains the cash from your bank account in two ways. First, a tire that is near the end of it's life doesn't hold air as well as a new tire does. This means burning more gas than you would normally have to. Second, worn down treads mean less grip, and that means your brakes have to work harder than is optimal. This results in having to replace brake pads before their proper time.
Rather than costing money, knowing when to purchase new tires may actually help you to conserve your cash flow. Knowing exactly when to buy can help with this.
There is no simple formula when it comes to making this decision. You could take the car's mileage and use it to figure out when you should need new tires, but this is not always a good indicator. Different drivers have different driving habits, and this may lead to unusual wear patterns on the tread. It's better to use indicators that are not so linked to time or distance driven.
One of the most common clues that your vehicle is due for new tires is when handling changes for the worse. It can actually be a very minor difference, but if it is a vehicle you drive often you won't have any trouble noticing. If steering takes more effort than it used to, or if driving through even shallow puddles starts your car hydroplaning, then it is probably time for new tires.
Another good way to tell is by periodically examining the Treadwear Indicator (TWI) bumps located in the bottom of the tread. Look for small raised lumps in the bottom of the treads. They can often be found by looking for a TWI marking on the tire where the tread and sidewall meet.
If the TWI bumps are below the tread across the whole width of the tire, then you are probably OK for the time being, assuming you haven't noticed any steering or handling problems. However, if the TWI indicators are flush with the surface of the tire, even on only one part of the tread, then it's definitely time for new tires.
When it comes to maintaining your vehicle, an ounce of prevention is worth a pound of cure. And it's usually less expensive.