Are your tires ready for the next road trip?

Should old tires be replaced?

Not necessarily, according to Dan Zielinski of the Rubber Manufacturer's Association. The problems are wear and damage not age.

"Warning signs include cracks, bulges, cuts and abrasions," Zielinski. "Those things can happen on any tire if it's exposed to the elements."

Yet, even tires several years old can perform admirably. Zielinski said the key is to maintain them properly.

Moreover, trauma can affect tires regardless of age. For instance, tire damage may be permanent if a driver hits a median strip or runs over a nail.

"Never fix a tire that has damage to the sidewall," Zielinski said

A major culprit is heat. Under inflated tires generate heat that, over time, can damage tires. The risk of under inflated tires is made worse during hot summer months when the outside heat can add to the stress caused by under inflation.

"Families stuff everything into their cars before going on vacation," Zielinski cautioned. "Extra weight increases tire heat and risk of failure."

In contrast, proper tire care can improve tread life and fuel economy. Your vehicle loses 10 percent in fuel economy on average for every five to seven pounds reduction in air pressure, Zielinski said.

How can drivers get the most out of their tires, even old tires? Zielinski ticked off several key elements:

• Check tire inflation monthly, especially if you're going on vacation. Extra weight adds to tire stress, and proper inflation helps keep tires from riding on the sidewall.
• Check for cracks, bulges and uneven tire wear. Such signs of fatigue may contribute to tire failure.
• Rotate tires regularly. This helps prevent uneven wear and may uncover problems with tire balancing or alignment. Rotation method varies as to vehicle you drive and tire (front-wheel vs. rear-wheel drive, conventional vs. steel-belted tires). Check manufacturer guidelines.
• Ask for plugs and patches when fixing a flat, not just plugs. Plugs may come loose and deflate the tire.
• Check anytime your vehicle hits a pothole, curb or gutter. Tires may be damaged permanently and need to be replaced. Telltale signs include bulging and cuts on the sidewall.
• Do not overinflate tires, which can cause premature tire wear and make tires more susceptible to road hazard damage.
• Do not fix sidewall damage including nail holes. Replace tires instead.

"The worst enemy for tires is always heat," Zielinski said. "This is especially severe in summertime if your car is over loaded and tires are under inflated."