I am working on putting together a 2013 taotao 125 quad with their 4-speed semiautomatic transmission. The manual is vague in terms of fill location and capacity for the 'gear box lubricating oil.' I believe that the transmission and engine share the same oil (the manual recommends 15W-40) sump, and there is no separate 'gear box' fill for oil...as compared to a CVT-type transmission where you would put a separate gear oil into the gear box. Is this correct?

 

You are correct. They share the same oil. We use a Castrol 10W-40 Motorcycle part synthetic oil. Been using it for years. 1 liter will do a full oil change.