I think I goofed.

I had a Nissan Xterra pulling a KZ Sportsmen Classic 19BH. The Xterra pulled the camper with no problems in the power side of things as it was rated to pull 5000 pounds and the camper loaded was pushing 3000 pounds. The only real problem was the Xterra wheel base was only 106 inches and there was way too much sway for comfort. I found a 2001 F150 xlt supercab at a local dealership and did a quick google search on the towing capacity for that year and line. 7000 to 8000 pounds came up so I figured it would give me over a foot longer wheel base and up my towing capacity a couple thousand pounds at least. Done deal. Love the truck. No rust, low miles, has a factory towing package. Can't wait for spring to hook up and go! Today I was looking into specs on Fords generic towing guide and see that with my axle ratio at 3.08 I actually only have a 2000 pound rated tow capacity. I ran the vin on Fords site and one spec does say 3800 LB(1724 KG) Rear Axle Assy. My questions are, what will happen if I pull the 3000 pound camper with the truck as is? Is it worth the money to get the ratio changed to up the towing capacity? Why does it have the towing package built in only to haul 2000 pounds. Is there a way to tell if axle ratio has already been changed? I think I goofed.