It is quite common to decrease the air pressure in tires to increase off roads capabilities. By airing down you enlarge the tire footprint… The larger the tire the bigger footprint you gain! When driving on snow and sand it is necessary to reduce the air pressure. On rough gravel tracks it can also be advantageous, because the ride is so much softer and easier for the passengers and the vehicle itself.
- Deflating and floating on snowDeflating and floating on snow
It varies between tire brands how effective airing down is. Always keep in mind that the thin sided tires can more easily be cut by sharp stones! Tire manufactures do not guarantee using their tires with low pressure. However it is just so much more fun! Air pressure is usually measured in pounds/square inch (psi). The largest tires (37″ and 44″) can go as low as 3 psi (and even lower in extreme situations). The smaller tires should not have less than 5 or 6 psi.
- Beadlocks prevent the tire to slip off the rim when deflated
Keep in mind that heat is a problem. Rubber wear and tear increases in the heat. This is not a problem when driving on soft snow, but
- Wrangler with 49inches deflated ”Irock” tires
can be an issue on hard snow and hot sand.
Also the danger of the tire falling off the wheel increases. One solution is to install beadlocks on the rims, or glue the tire to the wheel! During the trip it is highly recommended that you keep an eye on the tire pressure. Because the pressures changes depending on how high you are from sea level and if you are in low or high pressure weather.
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