Thank you everyone for all your help!
I don’t have a ramp…….maybe that would help? Also he has navicular so maybe he isn’t sure he wants to put allot of weight on just two feet at a time? He jumps into the trailer and doesn’t really take his time to put front feet than back feet slowly and kind of squashes me. I am going to work on slowing him down , because he seems to be rushing everything.
That was a good point GHFrider I found that he was just leaning into the pressure of the chest rope….he leans into me when I ask him to back and really only takes a step back then immediately forward again. Once he takes a step back, I reward him and release a little hoping I could just go step by step, but I found that really doesn’t work that well. I will try back with a command so he knows what I ask every time and I can also use a couple more tricks you mentioned. Maybe he just needs more time and repetition, so I will just spend more time trying to back him out.