Finally,    when    buying  tires,  before  leaving the tire    store,  there   are a   few things
to  consider:
- Road  hazard  protection: This    is  a   policy  that    protects    you against road
 hazards that would destroy the tire and not normally be covered under the tire
 warranty. Items such as twisted metal, nails in sidewalls, and impact breaks
 from slamming into a curb or a nasty pothole—essentially anything that
 brings about the demise of the tire will be covered under this plan. The way
 the price of the replacement tire is determined is by pro-rating based on the
 amount of tread remaining at the time of the tire failure. If 50 percent of the
 tire tread has been used, then the replacement will cost 50 percent of the
 original price.
- Mileage   warranty:   Some    tire    makers  warranty    their   tires   to  last    a   certain
 amount of mileage providing proper tire maintenance can be proven if the tire
 fails prior to its stated mileage. The important thing to keep meticulous
 maintenance records in the event you need to make a claim to replace a failed
 tire before its time. Once again, replacement price is based on the percentage
 of tread used.
- Nitrogen  filling:    A   lot of  tire    dealers offer   nitrogen    filling of  tires.  What    are
 the benefits of this? Nitrogen drastically reduces oxidation on the rim and
 inner-liner of the tire because oxygen is almost totally eliminated from the
 mix. Air is made up of about 78 percent nitrogen, 21 percent oxygen, and 1
 percent argon as well as other inert gases. The more oxygen you replace with
 nitrogen, the less oxidation takes place inside of the tire. Nitrogen-filled tires
 hold their air longer than oxygen-filled tires because nitrogen is comprised of
 fatter molecules than oxygen; therefore, it diffuses through tire walls more
 slowly because it has larger molecules. The temperature of nitrogen gas
 doesn’t fluctuate, which helps the tire pressure stay more consistent. As a
 result, the tire runs cooler because it remains properly inflated. This is one of
 the reasons that aircraft and racing tires use nitrogen. In short, nitrogen keeps
 the tire properly inflated longer than air, which leads to less rolling resistance,
 which leads to greater fuel economy and extends tire life.
- Lifetime  balance and rotation:   Some    tire    dealers offer   lifetime    rotation    and
 rebalance of tires once you initially pay for the tire balance. Ask about this
 because it is a huge savings and ensures tire longevity.
