We were towing a 25 foot Catering’s trailer and passing a truck slowly up a grade and we got close at one point but still in our lane and he laid on his horn and gestured a ‘’what the hell palms up ‘’. We kept going not sure what was going on. Once over the crest of the hill he came barreling down on us and tail gated within a few feet. We sped up to get away and change to the right lane and he decided to catch up again and began riding his front left bumper on our real right corner of the trailer touching at times . At this point we were doing almost 80 mph. Totally freaked us out and we went even faster but started to bullwhip a little . We slowly gained some distance but he still was trying to catch up. After an 1.5 hours we turned off at Santa Nella for gas and waited for him to pull in. Never saw him again and regretted not getting his plate or trucking co name. All of this was have behind us so it wasn’t possible to get any details. He was also straddling both lanes so we could not slow down and let him pass. It was reminiscent of the old movie duel which scared the shot outta me as a kid. Do truckers still communicate with each other via CB when they’re on the same highway ? Did anyone witness this Scary shit ?