A couple of years ago, one of the off road magazines did an article on wheel strength. I don't remember for sure which magazine it was, but they contacted TUV, a testing facility in San Diego, to see how strong various wheels were. Manufacturers send their wheels to TUV for testing before they assign wheel ratings.
The bottom line was that the M/T Challenger (16/8 wheel), despite a 3,000lb rating, was the strongest wheel of its size they had ever tested - steel or aluminum.
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96 2500 4X4 5sp 4:10 215hp SLT Horton fan,TST plate,AFC spring kit, advanced timing,4"exhaust,GearVendors,BFG 285/75/16 on Mickey Thompson Challenger wheels, K&N, Detroit Locker,50#Boost and Pyro guages, Aluminim flatbed, gooseneck and bp hitches,Helwig air bags with compressor, Helwig sway bar, Rancho 2" front lift w/9000 shocks all around, Preluber w/aircraft hoses,Hytec rear cover,PacBrake,McCleod dual disc clutch,numerous other accessories. Pull 11,000lb aluminum gooseneck horse trlr. and 14,000lb equipment trlr.