I am not sure exactly where you are seeing the tiny gouges. Can you save one of my photos and draw an arrow to the area you see where there is a problem.
I have since put the unit back together and into the mower - I used it last week on an acre property. The noise is still the same going forward and not in reverse. It does drive the mower OK but I don't know what is expected from it in the way of speed as it would bought used. It has not seen any steep hills yet either.
Thanks for writing back.
I have also posted other remarks on this site;
[h=2]Ferris H2222K Hydro trans.[/h]