what oil auto vs mercury 10/40 25/40 ect

[carvguy]

I have A 1987 Mercruiser Thunderbolt 5.0 305ci . I'm getting ready to change the oil and have called 5 different marine machanics and have got 5 different answers. Everything from 10w40 to straight 30 to only merc 25/40. what is your thoughts on this.

Thanks Carvguy

[bruceb58]

Yes!

I agree!

[Don S]

NOT another oil thread ................
Read this last one that kind of stopped a couple days ago. It should answer your question.
http://forums.iboats.com/mercruiser-i-o-inboard-engines-outdrives/merc-oil-vs-mobil-1-a-392463.html

[45Auto]

Mercruiser factory recommendation below. If you don't believe that thay know what they're talking about, then use whatever you want. Someone will post that whatever you use is the greatest oil ever made for boats!

[bruceb58]

45Auto always believes adding confusion to an oil thread is a good thing!

EDIT...hey where did the carb picture go?