18"x18" brick pavers work really well too I went and got a few from a buddy he had left over from a patioaxisg said:bishop gp said:Used my cherry picker a tow chain and my body weight bouncing on the the back of it to remove my deeply embeded jack stand from the now frozen clay of my back yard so much for "non sink" feet on thosebishop gp said:Tried to finish puttin new motor mounts in and watched horrified as the jackstands sank into the ground
I remember those days !! 3/4" plywood cut in 18"x18" squares helps spread out the weight but clay is def unstable unless its frozen or completely dried out.