Ok....according to the manual I'm good to 6500#....the trailer weighs 3800#. So I think I'm good with the hitch and receiver I have. I guess I should drop the diff cover and put some good 80-90 weight synthetic gear oil with posi treatment for good measure in it. I just plan on the flat prairie for traveling with this. And at a reasonable speed....lol.
FWIW I run 75w140 synthetic when towing.