Tires on collector vehicles often deteriorate while sitting idle for extended periods (rather than wear out), due to natural aging and oxidation, as well as ultraviolet and ozone damage. Here are some tips to protect your rubber.
Tires on vehicles
Place something substantial, like a wooden plank, under each tire so it is not in direct contact with bare ground. Better yet, use jack stands under the axles so that the tires don't bear the vehicle's load.
Do not park on black asphalt or other heat-absorbent surfaces, snow-covered ground or in sand.
For vehicles stored outside, cover tires with an opaque, waterproof covering so they are shielded from direct sunlight.
One of the best ways to preserve tires is to drive the vehicle frequently so that the oils in the tires can come to the surface during flexing to protect the rubber.
Unmounted tires and wheels
Don't leave tires in contact with solvents, such as oil or grease, as on oil-soaked floors. These materials will weaken rubber.
Store unmounted wheels and tires in a clean, cool, dry, dark and well-ventilated area. A dry basement is better than outdoors or in a hot garage or attic. Basements tend to remain cooler while the outdoors, garages and attics can experience large temperatures fluctuations.
Store tires vertically rather than stacking horizontally. Vertical storage reduces stress and possible distortion. If stacked horizontally, place on a clean wood foundation to protect them from dirt, oil and grease. Horizontally stacked tires should be piled symmetrically and not so high as to cause severe distortion in the bottom tires.
Stack whitewall or white-letter tires "white-to-white" and "black-to-black." Black and white rubber are compounded differently, so stacking all tires white side up can let the oils from the black sidewall migrate into the white rubber.
Cover stored tires with a sheet of opaque polyethylene material to limit exposure to oxygen and ozone. Better yet, store each tire in its own opaque, airtight plastic bag. You can get them at tire stores, or use lawn and garden bags. Tape the bag shut to prevent moisture from entering.
Tires should be stored so water cannot collect inside. Besides causing damage, moisture can be a breeding ground for mosquitoes and other insects. Water left inside a tire can turn into steam as casing heat builds up at highway speeds.
Mounted tires in storage should be maintained at 10 psi.
Check the age when buying new tires. It is possible that a tire has been on a dealer's shelf for many years, especially if it is an uncommon size (as might be used on a collector vehicle).
While tire dressings make tires look great, they can accelerate deterioration with foreign materials that can decrease the effectiveness of tire compounds that resist ozone cracking or weather checking.
Any tire that is more than 5 years old should be carefully inspected for cracking and probably be replaced, even if it has acceptable thread left.