Originally Posted by Jack2468
I was wondering if regular automotive engine oil, or diesel/heavy duty engine oil would work in a marine application.
The engine in question is a Suzuki DF140. The Suzuki oil is really expensive (like $9/quart for the old stuff and about $10 or $11 a quart for the new Ecstar stuff local to me), which seems expensive, especially for a 10W-40 synthetic blend. Not only is it expensive, the Suzuki dealer is pretty far from where I am located and inconvenient unless I need anything major done.
Would a quality SN rated automotive oil be ok to use? Preferably Mobil1 or Pennzoil Platinum or similar since Walmart sells them by the 5 quarts reasonably cheap and they are a quality full synthetic that perform very well in automotive applications.
Otherwise, would a diesel/HDEO like Rotella be better? I think they are designed to stand up in tougher/hotter conditions.
The last option is to just stick with OEM stuff, which is expensive and hard to find, but I'll use it if it truly is just the better option to stick with OEM marine oil in this application. If this is the best option, where can I find the Ecstar oil to order online for a fair price?
These suzuki engines appear to bee very similar to an automotive design, and are water cooled 4 cycle engines, just as cars are, so I would assume regular, quality automotive oil would be fine to use, am I correct or not?
Your owners manual tells you which oil to choose and I would listen to them over anything in a forum, which is the following - Should be easy to find, most likely in a motorcycle oil for that API. Not going to be much cheaper, I would choose Valvoline 4 stroke synthetic oil or conventional. Look around and you will find something.
"API: SE, SF, SG, SH, SJ(50 g)SAE: 10W-40"
