ALL Mercruisers?

[kmenard]

I am trying to find what oil my 2002 Gekko takes...is it true all Mercruisers take synthetic 20w50?

[oldjeep]

A mercruiser is an I/O. But in any event a merc 5.7 is a merc 5.7

 

The manual for your engine is here

 

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&ved=2ahUKEwiS8vvM0YDwAhUkB50JHRhXAjsQFjABegQIBRAD&url=https%3A%2F%2Fus.v-cdn.net%2F5020499%2Fuploads%2FFileUpload%2F35%2F24c9dbda1b871c01ec4324f4912a98.pdf&usg=AOvVaw0tO-lJVT36S-_y0DIWh3oY

 

And it says

25W-40 or a good quality 20W-40 or 20W-50. No requirement for synthetic

 

 

[DW]

@kmenard - That will work although if your question is that the only option, it is not. Several factors should enter your decision on which oil to use. Hours, ambient temperature range, previous type of oil used along with general engine health. Oil API rating is also something to note, although hard to find oils that don't meet the requirements when shopping via typical vendors. And in reality it is easy and common to overthink what oil to use. If you are asking because you are not finding synthetic 20W50, pay more attention to the latter number. I think you are from MN hence start ups could be in relatively cold weather with cold water I would go down on the first number. If you are happy with the oil pressure running 20W50 and can't find it, I would go with something like 15W50 or 15W40 as a substitute which are pretty common these days even at Walmart.

[oldjeep]

FWIW - when I had a Merc engine, I just used the quicksilver 25W-40 they recommended in the manual because it was cheap and I could buy it pretty much anywhere.

 

Should also say that my Inlaws have always just used 15w40 Rotella in the Black Scorpion Merc in their LXI.

In the end, they are all the same GM Marine crate engines regardless of who the marinizer was.

[kmenard]

Massachusetts...not quite as cold as MN...but...you know... :)

[oldjeep]

Hey, it is beautiful here in MN. It is around 50 degrees and it hasn't snowed in 2 days.

[thager]

Ha! Snowed twice yesterday in S. MN.

 

[ALPJr]

4-8” expected in New England overnight and tomorrow

[BraceMaker]

@oldjeep MerCruiser is Mercs stern drive and inboard engine trademark as well as the outdrives.

 

They have all their manuals available online but I have always liked the quicksilver branded oils from Merc other than the $.

 

http://www.mercurymarine.com/en/us/land/owners-manuals/

 

 

[ALPJr]

@kmenard, I’m pretty sure Mr. Wade only trusted Merc oil in his Flightcraft. ‘Twas a different animal and not sure if that correlates to your Merc at all though.

[Fastguy888]

Run Rotella T6 15/40 in my 1994 Mercruiser 454 EFI Ski without issues.