tow ball diameter
 

Does anyone know if the diameter of the tow ball is universal, I know that in the UK the hitch mount is different, they dont use the 2" square opening mounting.But is the ball diameter the same.
:)

There are several sizes that are used; 1 7/8, 2 and 2 5/16. You need to find out what the trailer has. Don't ask what idiot thought we needed 1 7/8. Typically the 2" ball is used and supports up to 5000 GTW. You can also get a system that gives are all three balls so you don't have to worry what the trailer has.

As for is it the same here as in Europe. They use 50mm balls there.