While you are not likely to put 4000 lbs of cArgo in it, you will likely be upwards of 12500-13000 lbs loaded which means a loaded pin weight (based on 20% rule) of 2500-2600 lbs. Do you have that much available payload and enough room in your RAWR?
What the towing guides Donnell you is you need to account for every option, passenger and gear in the truck and that decreases your payload. Best advice, go weigh your truck ready to camp. Weigh each axle on a separate scale pad. Then subtract the trucks actual weight front the trucks gvwr to get your available payload. Subtract the trucks actual weight from your gcwr to get your adjusted towing capacity. Finally subtract your actual rear axle weight from your max RAWR to see if you have enough room on your rear axle and in your payload to handle it. Chances are you will be fine, but I have had a f250 w/ the 6.4 that only had 2400 lbs available on the rear axle and 1500 lbs of available payload so calculate your numbers first.
2014 Chevy Silverado 3500 SRW Duramax
2011 Zinger ZT26BL-sold
2014 Sabre 34REQS
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