Proper tire maintenance includes measuring the tread depth to monitor when you have to change to new tires. In order for you to change all the four tires at the same time, you should rotate the tires. This will even out the difference in wear between the front tires and the rear tires and will make the tires last longer. The rotation should preferably be done when the difference in wear is 5/64 and you should change to new tires one you reach a tread depth of 5/32. If you change between all-season tires and winter tires, you can usually do the rotation at this moment. This might however not be enough if you drive a lot or if you have an electric car or a hybrid that tend to have a higher wear on their tires. If you have all-weather tires, then you are maybe not changing for another set during the winter, but you will then need to make sure that you take charge of your tire rotation.
Proper tire maintenance includes checking the tires for any cuts or cracks. Optimally you would do this every time before you drive, same way as an airplane is inspected. Since most people would feel that this is too much, then you should at least try to do it when you stop for gas. Topping up the tires with air should be done at least monthly and at the same time you should check the condition of the tire. The air pressure in the tires is important for them to perform optimally and have the correct contact surface area. Too low pressure leads to increased rolling resistance of the tires, which then leads to increased tire wear, higher fuel consumption and emission of greenhouse gases. Tire pressure can vary and should therefore be checked on a regular basis.
The tread depth doesn’t have to be checked every time you stop for gas, but if you measure the exact depth of your treads with a gauge, then you can better track the wear of your tires. Then when you measure if e.g. every month you can more or less figure out when you will reach the state when the tires are worn out and key properties will decline. With declining properties, the tires will be less safe, and the braking distance will increase and the risk for aquaplaning will increase. This is why it is important to change all the four tires to a new set. By changing only two tires you will have different grip on different positions of your car, and it can cause the car to over- or understeer. This far from being an optimal situation, this is why the rotation and maintenance of the tires is so important so that you always have four tires that are in good condition on your car.
For more information regarding maintaining your tires and checking the tread depth, visit: nokiantires.com