op, luv those z-turn mowers, I wish I had a bigger yard so I could get one of those :-)
I DON'T own one,
1. Air cooled v-twin
2. Hydrostatic transmission
I would switch to synthetic for both after break-in
Make sure you follow what is required for warranty.
You mean like one of these?
This one is Gravelys top of the line model with air ride seat, rubber isolated engine cradle, isolated foot platform, isolated seat platform and Kohler closed loop EFI. Not cheap but it is what we do for a living. One of the smoothest operating machines on the market today.
Part of my front yard.
I run amsoil in everything we own except my race car//street rod. That gets the "green" oil.