[quote author=erics76 link=board=11;threadid=17540;start=0#msg165643 date=1059535413]
I forgot about this, but it's interesting. A feed store around her has a 3500 diesel with a flatbed. For at least a year now, I see that truck with 4 square pallets of feed on it at least once a week. That's at least 8,000lbs. sitting on the rear axle. I keep thinking i'm going to see it on the side of the road, but I never have. Seems very scary to me.
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They probably have after-market springs, and more than likely are running load range G tires.

 

I have a stock SB and my overloads are off since I don't haul that kind of weight too often,,, but I did haul 37 bags of 80# concrete for 3000 lbs and the truck was basically level if not a hair lower. I'd say 3400 lbs for your tank would be no problem. Just remember, that makes your truck almost 11,000 lbs total!!!

 

I don't know if they're running after market springs or overrides, but I doubt it. The tires are the stock michelins, E-rated. When it's loaded, the bed is almost on the tires.