What happens when you hit a rock Marty? Our area is full of rocks,sometimes big ones like refrigerators and up,plus flat rock. Our farm was all done by hand early 1900's,some places clay tile is down seven feet,all done with pick and shovel and pan of water for grade
Shift down into granny gear on both the wheel and the tracks, let it work it up. We have had to on occasion back up a little, disconnect the boot, track forward while pulling the wheel out of the ground then get the backhoe or mini excavator to dig the rock out then track back, drop the wheel and reconnect the boot.
We had a big rock, just high enough would always bend a plow point back in the day. One of my uncles dug all day on it with the backhoe, finally had to dig a ramp on both sides, wrap several chains around it and pull with a tractor while pushing with the backhoe to get it out of the whole and to the ditch bank. Dad sold that rock 4 or 5 times before somebody finally showed up with a big enough crane to lift and load it. Had another one, they dug and dug, finally decided it was even bigger than the previous one, filled the hole in and farmed around it.