I was going to purchase some Yama lube gear oil 20w40 ... Is this OK or do you guys use something else. and while changing this you drain. Put in bottom bolt and fill until oil comes out of the middle bolt (Oil level bolt)thanks

 

The Manuel calls for sae 20w40 I cant find that in the stores here ..just 20w50

 

You can run 10-40, 20-50, anything will be fine.