tongue jack slipped

Did that once and learned my lesson. I haven't set the tongue jack down on blocks since. After my heart started pumping blood to my brain again it kind of made sense, at least in my case, even though I had "gotten away with it" many times. The foot of my jack is about 1/2 to 3/4 the size of the blocks I was using (lynx leveling blocks) and smooth on the bottom. The leveling blocks are smooth plastic shaped kind of like lego blocks for stacking. This means there was limited contact between the somewhat slick plastic blocks and the smooth foot of the jack. Very slight incline but raising the tongue enough to disconnect was enough to literally tip the scales. Fortunately I only had a couple of blocks stacked and it stopped moving when the tongue hit the ground. It could have been much worse. I did have the wheels chocked, but chocks can and do slip. I've never had mine slip or move with the actual jack foot resting on the ground and I have plenty of travel available in my jack stand. I only used the blocks to save time.

I have been looking at investing in better chocks but my wheels are set too far apart for many of the X-Chocks and the Fastway ONEstep. I like the idea of the ONEstep and have considered making my own.