towing capacity ???

[lewi]

I am considering buying a toybox trailer. I currently tow about 5000 lbs and don't have to slow down in the montains, doesn't shift down with the 350 trans on all but the steepist of grades. My thoughts are towing closer to 12,000 to 15,000 lbs loaded and how the truck will handle that. I have a new tranny cooler, 4 core radiatior, and rebuilt tranny and rear end. The moter is new 383 running 9 to 1 with edelbrock 600, headers and so on.

My question is ......Is anyone else already doing this? My other option is to keep the enclosed trailer I use now and buy a motor home, but that is alot more expensive.