Originally Posted by apachewhitesox
That is kind of what I have been doing I haven't stopped him from backing out at all. I simply try keep him calm and straight when he decides to back out. The more he realises he isn't stuck in there the less he seems to mind being in the trailer.
I just worry when he chucks his head up during his freak outs because I don't want him to hit the roof.
That's what I'm talking about with timing. You want to catch his anxiety before it hits the level where he throws his head up. It's not pretty when they catch their head just right and split their head open, bleeds a lot and leaves a nasty scar. The idea is bring him in, and send him out, YOU need to control his feet and keep his concentration on you.
So, walk up, get 2 feet in the body of the trailer, stop, count to 3 if he'll wait that long, back straight out. Go back up do it again, and again and again, until he doesn't want to do the head tossing any more, because he figures out he doesn't need to. You control every step he takes in and out and you control the timing. That way he learns: You're the boss, always and He can trust YOU to not put him in a position where he needs to panic.
If that means you walk up the ramp, 2 steps into the trailer, halt forward motion and cue him to back out, then that's what you do for a while. I'm guessing you don't have a head bumper which would be a great thing to protect him, but you can do it without it, YOU just have to be sharper about reading his body language.