I assume you mean "dual wheel", not "duel axle", right? Your truck has been modified (and the weight carrying capacity seriously compromised) by somebody fitting aftermarket wheels to it. It would have probably been sold originally with 18" tube type tires on split rims with dual wheels on the rear axle, and somebody thought they were making it safer by using alloy wheels intended for a 3/4 ton truck. It's a good-looking truck, but don't expect those wheels and tires to carry anywhere near the weight the bed and suspension system was designed to haul.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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