lower unit gear oil question - mercury 40 hp

[rslack29]

can i use automotive type gear oil in my lower unit? What type and weight?

thanks

 

[robert graham]

Re: lower unit gear oil question - mercury 40 hp

Only use Marine specific lower unit oil, it has special corrosion inhibitors for the marine environment. The Walmart brand is fine. Good Luck!

 

[DADDYRABBIT1]

Re: lower unit gear oil question - mercury 40 hp

No never use automotive gear oil in your lower unit, it does not have the same water resistance and auto gear oil will foam up and expand causing pressure build up.