I have a 99' Ranger 4X4 4.0L with a 106,000 mi that I'm using to pull my 13' Casita.. which is 1100# and with it loaded with gear and the bed of the truck 1/2 loaded with firewood I was still able to pull up steep hills in 4th gear with cruise on and the RPMs never dropped enough to even change gears... it towed all that without even blinking... I am having trailer brakes
added when I have a new axle
installed next week but that is more for resale value and a safety precaution... I would say 3400# sounds about right... because at 1500# my lil powerhouse didnt even know I had a load...always use 4th gear and below to tow..
As a matter of fact I plan on adding a lite hitch to the back of the casita so I can pull my jonboat behind it...its about abother 400# max maybe a 30# tongue weight
....I figure I can pull 2000# fairly easy..without straining the truck..