the shoulder of the road, and seek a safe stopping place, like a side road, open dirt surface, gas station, parking lot, etc…
If there is no safe place within a reasonable range, you have to stop, but you don’t need to replace the tire. Go over the guardrail and have a tow-truck drag the car. The risk in kneeling for a tire, regardless of whether the puncture is on the left or right, is too great. This is part of the reason why “Run-Flat” Tires (with a reinforced sidewall) are applied into new cars, allowing to run to the near tire shop (up to 80km and up to 80km/h) and replace the faulty wheel. Other solutions for flats include a foam that inflates and becomes stiff upon contact with air. This can be injected into a tire (used in cans sufficient for filling one empty tire in a normal car, or two semi empty tires), or be built into it (like in rally cars) and allow to drive for a few additional miles to a tire shop. The foam is not good for the tire and it’s also toxic.
Tires contribute to safety in being more comfortable and silent (which means more concentration on driving), resistant for failures (which causes a lot of crashes), and provide good stopping distances in emergency braking, and good grip all around, especially on slippery surfaces or on tightening corners. Tires will carry a profound effect even at slow speeds and on dry surfaces, for slight defects (old age, excessive mileage, reduced inflation). They are the most important safety instrumentation of the car.
My rules of thumb for tire safety are:
1. from a known manufacturer, preferably one made in Japan, the US or Europe. The tires should fit the car’s rim size and the required speed and load ratings. The tires should be as new as possible (At the very worst case, purchase tires up to an age of one year, provided they were carefully stored) and with an E and/or DOT and/or JS approval. You should strive for four identical tires and, in the worst case, two pairs of tires which are very much alike.
Your minimal requirements from a road tire should be: Treadwear below 500, Traction rating from B and above (not C) and likewise with temperature rating. If you have a relatively low annual milleage (under 20,000 kilometers as a rule of thumb) get relatively soft tires which a treadwear between 340 to 260.
2. . It only takes a quick minute, but it can save a lot of trouble and even save human lives. As you set out for work in the morning, take those ten seconds to look at all four tires, and when you are about to head back home, inspect them AGAIN. In long drives, inspect all four tires (including tire pressure) and repeat your inspection of the four driving tires after any stop along the way.
3. once every two weeks and before any long or demanding drive. The spare should also be inflated, once every month and before any long drive. If you drove a certain distance to the station, you might need to inflate an extra 10% or even more to compensate for the heat inside the tire. You will also need to increase the pressure when the car is loaded with passengers and/or luggage, or if it is set to drive in very high speeds. In those cases, meet the car manufacturer’s recommendations for tire inflation when the car is loaded (or semi-loaded) and for highway driving.
If in doubt, always over-inflate a tire rather than underinflating it. If the gas station has an old, knocked air pump, especially one with a cam-dial gauge, don’t trust it and use your own personal “pencil” tire gauge. It’s recommended that you always check with your own gauge, even when there is a good, digital pump at the station. Don’t trust the pressures that appear at the station either, but rather the specifications in your own car. Take the chance of inflating the tires to inspect them more carefully and to clear out stones inside the tread. Make an effort to install a TPMS on your car. It is highly recommended.
4. between 8,000 to 15,000 kilometers, or at an average of 10,000 kilometers. Move the tires from one rim to the far-end rim (front-right to rear-left and vice versa) without reversing their direction of travel. If you drive assymetic tires, just swap the two front tires with the two rear tires. Use the chance to have the tires fully inspected from the inside too, and clea