The OEM jack sank into the asphalt soon after I took the wheel off, the jack leaned forward and the van moved about two inches forward, enough for the jack to tip over.

I am off to buy axle stands and a new jack asap. My van isn't going anywhere for the time being.
No injuries but I wonder what could happen to people who just want to change a rear tire by the side of the road, could be dangerous.
