Hi folks! I have an ASW carbide 7150 with internal F-N-R. Since I bought it it has a gear whine, in forward only, and only when under power. When I opened up the trans, I found that the teeth were very worn on the drive shaft gear that the clutch mounts to. I replaced that today, but the whine still persists. I spun all the bearings and inspected all the gears while I had it open. All bearings spun freely and nicely. There did not seem to be any play in the gears and shafts.

Any suggestions what else to look at?

I assume the transmission was filled with gear oil and is not running dry? The axle brings are okay?

Yes, I changed the gear oil twice lol, just to make sure it was cleaned out good.

I had originally thought axle bearings, but wouldn't those make noise any time its moving, forward or backwards, whether under power or not?