The lady who drives usually literally crawls around corners with him on board, and no he doesn't scramble on the stop. I specifically stated ONLY when turning left, did I not?
Some history on this horse might be necessary here. He USED to be brilliant. I know he has been trucked and trailered up and down the state (BIG state here, we are bigger than TX and AZ combined) in all sorts of different trucks and trailers and he has always been fine. I had him transported to me by a trucking company which had screwed me over before, because they were the only ones doing a run down my way any time soon after I decided to take him on a trial. I now will never ever use them again.
Something went wrong on that truck and he scrambled badly (and fell in the truck) between prior owner's property and the transport company depot. Same driver picked him up next morning and drove him 2.5-3hrs to my property and he scrambled "around every corner". Driver said he was crawling. Driver was running very very late and these guys get told off if they're behind schedule so I seriously doubt that.
It took me AGES to get Monty onto a trailer again. Two months of training is what it took to get him beyond the top of the ramp. He got a horrible fright on that truck and then had to get back on it and go through the same again, whatever it was.
So, it is NOT friend's driving. She is very careful not to upset him, because if he scrambles her trailer gets damaged and it is BEAUTIFUL and only a couple of years old.
The other friend he has trailered with IS a bit quick when hauling but he's only trailered with her once. I've been using friend #2's trailer to train my boy to load, but I don't really want her hauling him again because I now know he scrambles... it was with her that I discovered the problem hadn't gone away with the loading issue.
Friend #1 has been trailering horses for years, and never had a problem, including with a couple of so-called problem loaders... and her current mare is also a scrambler, but never scrambles on her trailer with her hauling it.
This horse, I just remembered, has been hauled untied, and scrambled that time. I have been tying him fairly long to give him his head but now I'm wondering if tying him short would be something to try... will have to give it a go, but I also have to try the other bay (I know people who have had success switching bays).
Occasionally I do have to haul alone, so next time I do I will have to try tying the divider across, or removing it completely... but we'll have to see because hauling alone is very expensive for me, I have to hire a towing car AND a trailer and the nearest trailer hire place is an hour away so there's gas there and back, and 2 hours of my time (meaning trailer would have to be picked up the night before rather than the morning of)... 2 or even 3 days' trailer hire, car hire. Expensive exercise!