Car and truck tires are designed for traction, smooth ride (soft sidewalls), and regular use (so for high mileage have less internal lubricants in the rubber). Frequent use circulates the additives in the vulcanized rubber to keep the tires flexible yet give the best mileage.
Special Tires (ST) are designed with tread patterns for low rolling resistance for better MPG while towing, stiff sidewalls for high resistance to sway and twisting moments, ten times the lubricity additives to keep the rubber soft for long periods of non-use followed by short periods of operation at high speeds.
If you would like the absolute straight "skinny" on this topic feel free to contact the RV Safety Center tire engineer below:
Walter C. Cannon
RV Safety & Education Foundation
Everything else is "Caveat Lector"
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