It's bad enough that the manuals are not very clear, but throw in the fact that all manufacturers don't use the same method to determine a vehicle's towing capacity and you could find yourself getting agitated.
Which 4x4 Tow Vehicle
You need to figure out how much of tow vehicle you have and if it will tow what you want. You can contact local trailer dealers to get a Tow Vehicle Guide to help you find the right sized trailer for your tow vehicle.
Basic Terms
There is a little bit of terminology you can learn that will help you find out how much your 4x4 tow vehicle can tow. Sherline offers a Trailer Load and Balance Worksheet that will help take some of the guesswork out of the formula.Hitches
Once you know how much weight you can tow you can figure out which hitch will work best. This decision should be taken seriously because it is the bond between your tow vehicle and your trailer and there are many to choose from.There are several types of hitches to choose from and the type oftrailer you are towing will usually determine the type of hitch you'll need.

