Geesh, both motors getting roasted in 2000hrs....one has to wonder why.
Did you have to swap the old ones in when you bought new ones? (some places want the core to rebuild them).
I'd tear one of them apart to see why it blew up at 2000hrs (might even be able to fix them). Watched several youtube vids on drive motor repair, and it seems the number one cause is not changing drive motor gear (planetary) case oil. It seems the oil degrades to the point the gears start shedding metal, and the heat wears out the seals. Eventually, the gears self destruct, or the contaminated oil from gear case gets into the motor, and wears it out.
BTW - thanks for following up on your thread...very helpful to all when problem is shared and solved.