Combines 1992 1680 torque sensor problems

any chance the drive belt from transmission to the pulley that drives the variable pulleys is stretched enough to fail under loadIJ

I change all both belts, the one from the clutch to the gear box and the rotor drive belt. What happens is that under full load on the rotor the belt seems to slip.

I was going to post the same question today. I often have that problem on my 1989 1680. Yesterday in very poor flax, when I would hit the better swaths my rotor would fall from 950 all the way down to 750 while the engine RPM fell very little. In desperation I found an old can of belt dressing and sprayed both the rotor belt and the big triple v-belt beside it. It solved the problem. What do I do nowIJ Do I keep using belt dressing, or does that mean it's time to change the belt or beltsIJ (I should have only done one at a time, to see which one it was, but at that point I wasn't thinking of that.)