About took that fender off there. In all reality we have had a few guys wreck the truck or worse yet, one guy wreck the truck and trailer, put the tractor on its side, and end up with a broken arm. Looking at your rig you have zero weight on the back of that truck unloading the tractor. What happened to the guys I am talking about is the same senerio and the truck took off down the drive way. As this happened one guy lost a ramp and over the tractor went. He broke his arm when he jumped clear. I am not the safety police but you should throw a jack stand under the rear of the trailer and make sure you park on a flat area.
Just something to think about.
Chris