We replaced the up/down gearbox several weeks ago on our LT 70. We then encountered a new problem, rare at first, but getting much worse, to the point we shut the mill down. The head free falls. Usually it happens when you position it for a new cut. However, it has happened in the cut. They sent a brake assembly add on but it was meant for the LT 40, not the 70. They put it on anyway, and didn't seem to make any difference. They were on the phone with WM all Friday afternoon. They can't figure it out, except thinking it might be a programming problem in one of the units in the electrical control panel. Anyone ever had this on a 70? We have to get up and running.