lower unit oil

[lonewolf5347]

any one no if there is a difference in auto gear oil 80-90w example castrol hypoy-c gear oil for the lower unit on outboards compare to marine lower unit oil .or just the price.does marine lower unit unit oil have a anti-foam addtitive in it ?

 

[Down South]

Re: lower unit oil

I dunno if there is a differance or not. I've wondered about this a few times myself. I go ahead and spend the extra bucks and get the same brand oil as the motor since usually it never takes more than a few tubes and it's not changed that often.<br />

 

[byordy]

Re: lower unit oil

My understanding is that the marine gearcase lubricant has an additive that will allow it to mix with a small amount of water and continue to lubricate. Because of this a small leak will not cause the water and lubricant to separate and cause a failure of the gear case.<br />Bill........

 

[lonewolf5347]

Re: lower unit oil

well just to be on the safe side , i drop the old oil which was castrol 80-90w had about 2 runs on it look crystle clear ;but who knows ;and just replace it with marine grade lower unit oil everyone thanks for your reply and comments