Prowler V6-3.5L VIN G (1999)
Tires: Testing and Inspection
Checking Extended Mobility Tires
When an Extended Mobility Tire (EMT) is driven without air pressure, the overall temperature of the tire will be higher then its normal operating
temperature. This is caused by the increased rolling resistance of the tire. The sidewall of the tire is one area that will be at a higher then normal
operating temperature, and could the area of the tire that is at the highest operating temperature. This is caused by the edge of the wheel flange rubbing
the sidewall of the tire when the tire has very low or no air pressure in it. For this reason an EMT tire must always be inspected for excessive heat
damage when the tire is dismounted for repair.
The entire inner surface of the tire needs to be inspected for damage caused by excessive heat build-up. This type of damage is detectable by cracking
and discoloration of the rubber on the inner surface of the tire. Excessive heat damage can also cause an excessive amount of powdered rubber to be on
the inside of the tire.
The sidewall of the tire is the other area that can be damaged by excessive heat build-up caused by its contact against the flange of the wheel. This type
of excessive heat damage is diagnosed by the thorough inspecting of the inner and outer sidewall of the tire. The sidewall on the inside and outside of the
tire needs to be thoroughly inspected approximately one inch down from the bead of the tire. During inspection, carefully look for discoloration and/or
cracking of the rubber material on both the inner and outer sidewall surfaces of the tire.
If discoloration or cracking is noticed on any of the inner or outer tire surfaces during inspection, the tire must be replaced and not be repaired. Repairing
an EMT tire that has been damaged by excessive heat may result in the sudden and total failure of the tire
