Here ya go. I had put this in your General Chat thread first, but it belongs here.
w1ngzer0,
Be careful with those ratings. They are usually computed with the basic truck as light as possible, i.e. with no options and one 150# driver. The truck will have a fixed GVWR (Gross Vehicle Weight Rating) and a GCWR (Gross Combined Weight Rating) for towing.
The "payload" comes form the GVWR minus the actual weight of the truck. So as long as it's just you and you havn't added a bunch of amps and extra batteries, etc. then the amount you can actually carry may be close to what's published in the brochure. The best thing to do is take your truck to a certified scale and weigh it (full of fuel and loaded with driver and passenger or ballast). GVWR minus your actual weight = Payload.
The same with the tow rating. Truck weight plus trailer weight = GCWR. You have to be careful of the trailer tongue weight though, that gets added to the trucks weight. For instance, my trucks GVWR is 6600# and the GCWR is 13000#. My truck, loaded with family, fuel and firewood weighs ~5850#. In theory I would have an effective towing capacity of (GCWR 13000# - 5850#) of 7150#. My travel trailer weighs 6100# when we're loaded to camp for a week so I should be ok, right? Well, the tongue of the trailer weighs 650#. Added to the trucks weight of 5850# and now my truck is at 6500#, uncomfortably close to the 6600# GVWR. Could I tow the 8000# that is advertised in the brochure? IMO, not safely and not staying within the limitations of the truck.
Be careful with those ratings. More at
http://rv.net/forum/Index.cfm/...0.cfm
Ty