Quick oil advice needed - Not another oil thread!.

[h2odick]

Good morning/afternoon folks!

Just need some quick input, dont mean to start an oil thread/flame war or anything. I'm going to be purchasing some oil for an oil change, and need a hand.

I'm most likely going with Amsoil (as i'm a preferred customer, and its cheaper than Mobil 1 15w-50)
My volvo manual calls for SAE 30, 15w-50, or 20w-50.
From what I see, there is two options for me (in regards to Amsoil)
This one: (15w-40 "Diesel and Marine")
AMSOIL SAE 15W-40 Heavy-Duty Diesel and Marine Motor Oil
or This one: (20w-50)
AMSOIL SAE 20W-50 Synthetic Premium Protection Motor Oil

Which one would be more appropriate for a 7.4 volvo being used in southern California, Arizona, and Nevada. (Decent temperatures mostly year round (50-60f and up..)

Thanks.

 

[jestor68]

Re: Quick oil advice needed - Not another oil thread!.

If one is a synthetic and the other is not, go with the synthetic. If both are synthetic, go with the least expensive.

 

[wrench 3]

Re: Quick oil advice needed - Not another oil thread!.

Mercruiser switched everything to 25W40, but I can't buy that wholesale. I asked the rep from our oil distributor for advice and he said he's using 15W40 in his boat. So thats what I'm using in mine.

 

[agallant80]

Re: Quick oil advice needed - Not another oil thread!.

The first number is only the oil weight when it is below 50 outside. Sense we use our boats during the summer and warm weather I would worry more about the 2nd number. Mercruiser says you can use strait 40 in it.

 

[UncleWillie]

Re: Quick oil advice needed - Not another oil thread!.

Is the engine going to be commercial service?
If you are typical, you will not put enough hours on the oil, before the annual oil change, to make any difference.
The least expensive option would be indicated.

If you were to change the oil in your car every 1000 miles, it wouldn't make much difference which oil you used.

A famous quote around here, "New, cheap, clean oil is better than old, dirty, expensive oil any day."

 

[frantically relaxing]

Re: Quick oil advice needed - Not another oil thread!.

If you don't need synthetic, 15w-40 is great stuff.

If you need synthetic, if you can't find 20w-50, then ANYw-50 will be fine...

just another

worth...

 

[emilsr]

Re: Quick oil advice needed - Not another oil thread!.

There is another marine option, that's what I've been running.

AMSOIL 10W-40 Synthetic Formula 4-Stroke Marine Oil

 

[h2odick]

Re: Quick oil advice needed - Not another oil thread!.

Right on, thanks for all the feedback guys, I really appreciate it. No, my boat wont be in commercial service, just leisure cruising and the occasional WOT runs across the lake. We do boat year round, but I'm definitely not racking up a ton of hours. I do personally believe in using a good synthetic oil (my boat, diesel truck, and sand toys deserve it), it also makes me feel a little warm and fuzzy inside

 

[BrianCinAz]

Re: Quick oil advice needed - Not another oil thread!.

There is another marine option, that's what I've been running.

AMSOIL 10W-40 Synthetic Formula 4-Stroke Marine Oil

I would agree. The diesel oil in the first post is not for gas engines. The additives for neutralizing acids is a different formula.

15W40 is better than the 20w50 because our engines run cooler than auto engines. Our stats are 160˚ whereas a car engine is using a 195˚ for lower emissions.

 

[h2odick]

Re: Quick oil advice needed - Not another oil thread!.

Actually, according to Amsoil in regards to the 15w-40 Diesel/Marine Oil (which is also a synthetic like the 20w-50 i posted) Amsoil states:
"AMSOIL Synthetic Heavy Duty Diesel and Marine Motor Oil is recommended for diesel engines, gasoline engines and other applications that require any of the following specifications.."
They also mention recommended drain intervals for gasoline engines using this oil.

I would generally agree that diesel oils are formulated differently for those engines, I only noticed it when looking for a new suitable oil because of its SAE rating..

 

[deafwish]

Re: Quick oil advice needed - Not another oil thread!.

For the sake of a couple of HP, always go the thicker viscosity - especially in marine applications.
Regardless of thermostat temp's between cars & boats, oil will shear MUCH faster in a marine environment.
Running a boat at WOT is like a car being run at 100% load on a dyno, at max RPM for considerable time periods.
Either find a full zinc shear free product, or find the best PAO/ Ester based product (with high zinc) of a 15w50, 20w50 or 20w60.
Your oil pressure & engine will love you for it.
p.s. Do a Google search on VI Improvers.

 

[TyeeMan]

Re: Quick oil advice needed - Not another oil thread!.

If your manual calls out a straight 30 weight, you could also use the Amsoil 10W-30 Four Stroke Marine Oil. I use that in my Volvo 4.3L H.O. and it loves it. If I'm not mistaken the data bulletin on th 10W-30 and 10W-40 calls out using these two oils in place of or instead of 15W-40. I too use Amsoil in everything I have, , the advantages of synthetic far outway using any dino oil. IMO.

 

[HT32BSX115]

Re: Quick oil advice needed - Not another oil thread!.

[h=2]Quick oil advice needed - Not another oil thread![/h]

Um, yes. It is.

If you don't want to use what the manufacturer suggests using then use what ever you want. EVERYTHING has been tried with good results.

You could use what I use (in my sig) but I am not allowed to tell!

My last boat engine (1966 Mercruiser ) went 39 years before I sold it. It got every type of oil that was the cheapest. It never had the head or pan off.......

Marine engines don't usually die from the type of oil used, they usually die from lack of maintenance.

 

[Chris1956]

Re: Quick oil advice needed - Not another oil thread!.

Gee, I think you ought to use what the manufacturer recommends. A sterndrive engine typically has much more demanded of it than an auto engine, although they are very similar in design. Automotive multi-vis oil is simply not suitable for strerndrives, which is why a SAE-30 or SAE-40 or some special FC-W oil is specifically recommended.