Ideally you should attempt to get the weight off of tires when an RV will be in storage for a period of time. But, this is not always practical or possible. If the weight can't be removed, at a minimum you should try to move the RV every three months to prevent tire flat spots and ozone cracking at the tire sidewall flex point. Flat spots will usually disappear after the tires warm up and travel for a distance, unless the vehicle hasn't been moved for six months or more.
There are actually several reasons for blocking tires. The first step is to make sure the RV is as level as possible so more weight isn't on one tire than the others. The perfect scenario would be to store the RV and its tires in a cool dry, covered area, but as we all know this is not always possible either.
Storage surface areas can cause your tires to age prematurely. You don't want to leave the tires in contact to any heat producing material or petroleum based material like asphalt. You also don't want them exposed to constant cold or moisture, like sitting on the frozen ground. The wood acts as a barrier between the tires and the ground surface they are being stored on. The proper storage steps would be to clean the tires, cover them to protect them from harmful sunlight and UV rays and inflate them to the pressure indicated on the sidewall of the tires.
It is extremely important that the blocking you use is wider than the tires tread and longer than the tires overall footprint. If not the steel cables in the tires sidewall can be damaged which can also result in premature tire failure.
Also, you can use Lynx Levelers, just make sure you follow the directions above.
Copyright 2007 by Mark J. Polk, owner of RV Education 101
RV Expert Mark Polk, seen on TV, is the producer & host of America's most highly regarded series of DVD's, videos, books, and e-books. http://www.rveducation101.com/
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