I just finished fabricating a chute to pull 4 poly conduits into the ground behind the ripped shank of a D9 And have a D8 in the shop that a hard rock ripped the entire Ripper mount right off the back of the tractor Bending the 1 3/4: thick mounting plate and snapping 18 inch and a half studs like they were made of plastic Some rock is so hard that even a rock saw has problems cutting a trench through it