When I put mine in storage I just put 4 wood slats behind the tires, then back up onto them. I'm not sure that rubber mats are good for long term storage.
I've heard that asphalt leaches out stuff from the tires
I've heard that concrete leaches out water
Is this true? I don't know, but the simple solution was these 4 wood slats that are easy to use and I store them in the bumper. I take it out of storage every 2 months and drive it home then back to storage, about 42 miles round trip.
From the Goodyear site:
Ideally, a vehicle in storage should be placed on blocks to remove all weight from the tires. If the vehicle cannot be put on blocks, follow these steps for tire protection:
- Completely unload the vehicle so that minimum weight will be placed on the tires
- Inflate tires to recommended operating pressure plus 25%. Ensure that the rim manufacturer’s inflation capacity is not exceeded
- Be sure the storage surface is firm, clean, well drained and reasonably level
- Avoid moving the vehicle during extremely cold weather
- Move the vehicle at least every three months to prevent ozone cracking in the tire bulge area, as well as “flat-spotting” from the prolonged strain of sidewall and tread deflection
- Adjust inflation before putting the vehicle back into service