What weight oil in lower unit ?

[Woody]

my manual only says super duty lubricant !!!! can i use car diff oil ?

thanks Woody

 

[Plainsman]

Re: What weight oil in lower unit ?

I'd say no. The reason being that marine grade oil has additives that help protect against moisture.

 

[tashasdaddy]

Re: What weight oil in lower unit ?

walmart sell marine lower unit oil, at a reasonable price 80/90 weight. they also have the pump, which makes it easier to put in.

 

[Texasmark]

Re: What weight oil in lower unit ?

Lower unit oil has a sticky additive that improves it's ability to stick to and stay stuck on metal parts preventing corrosion even though the oil may contain significant water.

WW also handles Pennzoil brand marine lubes and you might try them. I have Penn full syn in my 90's lower unit. And on the pump tas mentioned, I'll never attempt to fill another without one.

Mark

 

[DHPMARINE]

Re: What weight oil in lower unit ?

Why not just use the specified oil?

Vegetable oil will work to some extent.Hair gel to a lesser extent.

Actually automotive differentials have a large diameter ring gear.Much larger than your Merc's forward,reverse and pinion gear combined.It turns a lot slower.So the oil it uses is different.

Your Merc gearcase churns at idle (750 rpm) Then you hit it,and it is churning 5,000 rpm .In seconds. ......

Why fool around ?

DHP

 

[Scaaty]

Re: What weight oil in lower unit ?

I've pulled a lot of old OB gearboxes apart. Just one yesterday. Black Car diff oil and water comes out of a lot of them. Doesn't seem to mix at all. OB gear case oil holds the water in suspension (milky), and does little damage compared to a gear or bearing sitting in solid water.

 

[Woody]

Re: What weight oil in lower unit ?

thanks for all the advice guys !!! we don't have wal-mart here in aus !!! i live in a country area and there is only one boat shop 30 klm's away and they charge like wounded bulls !!! i have some diff oil in my shed and thought i could save some time and trouble and money but i guess i'll have to get the right stuff !!! i don't even know if it needs any , i was thinking about checking it the other day and thought to myself what will i put in there if it's low ??? is a synthetic oil better ?

thanks Woody

 

[Plainsman]

Re: What weight oil in lower unit ?

thanks for all the advice guys !!! we don't have wal-mart here in aus !!! i live in a country area and there is only one boat shop 30 klm's away and they charge like wounded bulls !!! i have some diff oil in my shed and thought i could save some time and trouble and money but i guess i'll have to get the right stuff !!! i don't even know if it needs any , i was thinking about checking it the other day and thought to myself what will i put in there if it's low ??? is a synthetic oil better ?

thanks Woody

You could get it online and not pay his price.

 

[AMD Rules]

Re: What weight oil in lower unit ?

Woody... it would be a good time to update your member profile to show your location (see under your user name). Sometimes, the response may be unique to your geographical location. Just a thought