Originally Posted by RangerJay
I'd agree that this is likely a brake problem - but regardless - it might be helpful to also get an opinion from Hensley by giving them a call - I'm sure they will ask you a couple of specifics about your setup - which should lead you to being able to eliminate the hitch as a possible source of the issue.
I believe that I will call Hensley tomorrow.
We went about 140 miles today, with some grades as steep as 8%, with no problem. The only change that I made was to increase the trailer brake controller gain setting from 7.5 to 8.0.
At this point, I am unsure of the cause of the problem. We will continue on and monitor the situation.
Many thanks for all of the suggestions from everyone.