Hello: The wife and I bought our first RV last year: a 25 foot Springdale trailer. We took it out a couple times last year, no issues. This last week (Labor Day week) we took the trailer down to the beach and stayed in one of the State Parks, full hookup site. Again, no issues until we were packing up to leave. But first... When we got to our site, the set up was as follows: get the trailer centered on the pad; drive up on a couple blocks to level side-to-side; chock the wheels; unhitch from the truck; adjust jack to level front to back; deploy the four stabilizer jacks on each corner; hook up water, power, and sewer; unfurl awning. When it was time to leave, I started the process in reverse. First I rolled up the awning. Then I started to retract the four stabilizer jacks. I started with the front right jack, then the right rear, then the left rear, and that's when it happened. As I started winding the 3rd stabilizer jack up, the trailer rolled forward and to the side a bit! Shook the whole thing. And the front electric jack came completely off it's blocks, and was suspended in the air. Had it not been for the remaining front stabilizer jack, the front of the trailer would have come crashing down. Who knows what kind of damage to the jack that could have incurred. I quickly got the blocks back under the front jack, raised it up a bit, and quickly got the hitch backed up and hooked up. I've been trying to diagnose why this happened; it hasn't happened before but as I said, this was only our third time to use it. My only thought was that I was going to wait to empty the gray and black tanks as my last chore. Could the weight of those two tanks (both about 2/3 full) have altered the center of gravity and caused this? However, last year we stayed at a KOA that didn't have sewer connections at each site, you dumped on your way out. And we didn't have this kind of issue then. Any and all thoughts are appreciated. Thanks.