Synthetic Oil - Opinions please

[jlinder]

It's that time to winterize the boat. Going through all the steps, including changing the oil. Engine is a 1988 5.0L GM engine. Has always had standard oil as used by a marine shop (they changed the oil in the past).<br /><br />I love the synthetics. Use them in my cars and swear by them. Seem to lube better and engine seems to stay cleaner inside (looking in from oil fill cap at rockers).<br /><br />What about in this engine? Not spec'ed for it since synthetics were not popular when it was made. Any problems using synthetics on the older engines?<br /><br />Also, what about multi-viscosity? Synthetics seem to only come in multi-viscosity, but I think I remember seeing that maring engines prefer single viscosity oils. Thoughts?<br /><br />I know there is a lot of knowledge out there. Thanks in advance to everyone who replies and shares theirs.

 

[Scaaty]

Re: Synthetic Oil - Opinions please

I refuse to get involved in anymore oil arguments myself, but I use what the book calls for.

 

[RedRangerVIP]

Re: Synthetic Oil - Opinions please

I run 30w Royal Purple in my boat engine. It is a synthetic. I haven't run it long enough yet to give to much of an opinion , but my brotherinlaw runs it in his 3.0L and loves it.You are going to hear a lot of different opinions about running the synthetics in your rig. In my opinion they are a better lube than the old dino, but that's only my opinion.

 

[Fishermark]

Re: Synthetic Oil - Opinions please

<br />Confused about the "eeks" above?<br />See this post!<br /> LONG oil post

 

[Bondo]

Re: Synthetic Oil - Opinions please

Ayuh.............<br /><br />Personally, I run Mobil 1 in 15W-50........<br />a 90something 4.3LX.... been 6 or 7 years now....<br /><br />You can find Everybody elses Opinion at the link that Fishermark has posted............

 

[jlinder]

Re: Synthetic Oil - Opinions please

Fishermark,<br /><br />Thanks for the link. I remembered the post, just couldn't find it for reference. It appears that if you get 10 boaters in a room you get 13 opinions.<br /><br />I came away with the following:<br /><br />1. Tendency toward the opinion that you should not use mult-viscosity oil.<br />2. Go with the good stuff. Oil is much cheaper than an engine. ( I have always felt it is cheaper to use the best now than repair later.)<br />3. A lot of opinions on using what the manufacurer reccomends.<br />4. A log of opinions on not needing to use what the manufacturer recccomends as long is it meets or excees all the specs.<br /><br />My question may be better put like this: When the engine was built (1988) synthetics were a much newer product and we did not have the experience with them we do now. Engines did not use or have synthetic oils reccomended.<br /><br />Now we know a lot more about how they work, and how they stand up, and the long term effects on the engines, do you use synthetics?

 

[Don S]

Re: Synthetic Oil - Opinions please

Jack<br />Just go to that "Long Post" and pick out what you want to hear. Use that type oil and change it and the filter regularly and your engine will not die because of the oil you use.

 

[rodbolt]

Re: Synthetic Oil - Opinions please

hello<br /> I am with Dons<br /> I have never in 30+ years of playing, actually seen a motor die cause of oil changes<br /> my poor chevy truck has done the past 180K with one oil change, two if you count the time the filter blew off and I drove it for a bit with almost no oil. even though the gauge stayed at 30 psi. most marine engines die a slow death of neglect. either the cooling system/manifold/risers kill it or fuel system maint does,<br /> but never have I seen an oil grade,as long as the recommened grade was used, related malfunction on a marine engine. my recommendation is use wally world oil and filters and save your money for pump kits, manifolds and risers.<br /> most boats die cause the owners says it always ran ok and we never fixed it befoire it broke.<br /> maybe a good deal on a grocery getter but not on a high performance package.<br /> dont sweat the oil. how many hours a year are you actually going to put on the oil?<br /> if money is tight, use the wally world stuff and keep up on the water pump,manifold and riser maint/replacements

 

[Buttanic]

Re: Synthetic Oil - Opinions please

DonS and rodbolt you guys nailed it. If using oil not recommened by the manufactuer or cheap oil was a big no no the shoulders of the roads would be littered with broken down cars. The only oil related failures I have ever seen are lack of oil failures from puntured oil pans or other oil leaks that run the engine dry.

 

[WillyBWright]

Re: Synthetic Oil - Opinions please

MerCruiser oil is a multi-viscosity oil (25w40). If you can find a synthetic 25w40, then fine. Even a straight 30 would work. But I've never seen anything other than 5w30, 10w30, and maybe 10w40. None of those would be appropriate except in cold climates. I don't think Atlanta would qualify.<br /><br />There are a few advantages to synthetics including better lubrication and tolerances to extreme temperatures. In a boat, the extreme temps should never be a factor. If it is, you have worse problems. Synthetics also stay thinner at cold temps making starting easier. Again in a boat this should not be a factor, especially in Atlanta. That leaves better lubrication. Longer life is decieving in that oil gets combustion by-products that contaminate the oil. It doesn't matter which oil you use, the contaminants pollute the oil all the same. So I can find no practical advantage to using a synthetic in a sterndrive. However if you can find an appropriate viscosity, it can't hurt.<br /><br />4-stroke outboards do use oils like 10w30 and synthetics are much more popular in those. There I see absolutely no disadvantage to using synthetics and if I had one I would.

 

[KaGee]

Re: Synthetic Oil - Opinions please

There outta be a "lock out" feature, keeping any more new posts containing "oil recommendations"....LOL!<br />