According to the Rubber Manufactures Association (RMA) under-inflation is the leading cause of tire failure. As many of you had noticed the “suggested amount” of air for your tires as specified by Porsche is shown on your vehicle’s front/rear trunk or the door edge of your vehicle. It is also listed in the owner’s manual or should be given to you when you purchase new tires.

Here are a few tips: 1. On a regular basis visually inspect your tires to make sure there are no nails or other objects embedded that could poke a hole in the tire and cause an air leak. I once found a screw in one of my brand new tires on my way to Miller Motorsports Park on my way to my first DE…I’ll save that story for another occasion.
2. Check the sidewalls to make sure there are no gouges, cuts, bulges or other irregularities.
3. Verify proper tire pressure once a month and before every long trip. Don’t forget to check the air pressure on your spare tire as well.
Did you know that air pressure in a tire goes up (in warm weather) and down (in cold weather) one to two pounds for every degrees of temperature change? For this reason you when you check tire air pressure, make sure the tires are cold – meaning they are not hot from driving. While some people think that the term “cold” tire relates to the outside temperature, it really has nothing to do with the weather. It can be 90 degrees outside and your tires can still be considered cold. Rather, a cold tire is one that hasn’t been driven on for at least 3 hours, which is the optimal time to get an accurate pressure reading. A tire that has been driven on for short distances – even just 1 mile – is no longer considered “cold.” If you do not have the luxury of having your own compressor at home and you will have to drive down to your local service station to get air. Check and record the tire pressure while your tires are cold and add that number of pounds needed when you get to the air pump. Make sure you use an accurate tire pressure gauge. Some of the built-in tire gauges found at gas stations may not give you an accurate picture of how many pounds of pressure you just put in. It is normal for tires to heat up and the air pressure inside to go up as you drive. You should never “bleed” or reduce air pressure when the tires are hot.

Alignment

Misalignment of wheels in the front or rear can cause uneven and very rapid tread wear and should be corrected by your local mechanic or tire dealer. If your tire dealer doesn’t have the equipment to do alignments, ask them to refer you to someone they trust. Have your alignment checked periodically or whenever you have an indication of trouble such as “pulling” or vibration. By pulling I mean letting go of the wheel on an empty flat level road and seeing if your car veers to the left or right of your lane. If the car veers, you should first make sure all of your tires have the correct tire pressure before spending the money to get your car aligned.

The technical definition of balance is the uniform distribution of mass about an axis of rotation, where the center of gravity is in the same location as the center of rotation.

An out-of-balance tire and wheel assembly:

o Degrades ride quality and driver comfort. o Shortens the life of tires, bearings, shock absorber, and other suspension components.

Vibration is the most noticeable effect of imbalance.

o It is dependent on vehicle speed and may be felt in the steering wheel, seats or floor board.
o It often first becomes apparent between 40 and 45 mph and changes in magnitude with greater speeds.

Properly balanced tires are important for driving comfort and long tire life. Unbalanced tires can cause vibration, resulting in driver fatigue, premature tire wear and unnecessary wear to your vehicle’s suspension. Tires should be balanced when they are mounted on wheels for the first time or when they are remounted after repair. Tires should be rebalanced at the first sign of vibration or “shimmy.” Vibration may also be due to misalignment or mechanical problems.

For sake of example, assume you have driven your tires 5,000 miles since their purchase and it’s time to rotate. Over the miles, turning left and right, hitting bumps and potholes you could not see or avoid, and driving down uneven road surfaces have led to uneven tread wear on your tires. Perhaps a pothole has knocked-out your vehicle’s alignment (this creates uneven tire wear). Well, besides rotating the tires and getting an alignment to set things right, you should also rebalance the tires. Even if you can’t feel vibrations, they are present. The uneven tread wear has created an imbalance that generates excessive heat and wear on your tires! Considering the hundreds of dollars you spent on your tires, a rebalance is a wise expenditure. Most tire stores sell a Lifetime Balancing program. For a nominal, one-time charge you can have your tires balanced at every rotation.

Tread

Tires MUST be replaced when the tread is worn down to 1/16 of an inch in order to prevent skidding and hydroplaning. An easy way to test this depth is to place a penny into a tread groove. If part of the Lincoln’s head is covered by the tread, you are driving with the proper amount of tread. If you can see all of his head, it is time to take a trip to your tire dealer and spend some money.