Motor Oil

[OKWAKEBDR]

I've searched, and I know this topic has been discussed several times, but nothing is real recent, so I thought I'd bring it up again.

My engine is slightly low on oil (probably 1/2 qt). It is getting close to oil change time, but I thought I'd just add some until I can get it in to the dealer. (The dealer is WAY out of my way.) In my 12+years of inboard ownership, I've never actually changed the oil, had to add any, or even really paid attention to what type of oil is going in the boat - I've just let the dealership do it. So, I checked the manual and it calls for SAE 15W-40 "GF-4/SM". I can't find that stuff anywhere. All of the 15W-40 is diesel oil. Rimula or Rotella seems to be the popular brand, and I've heard that some people use this in their boats also.

So, what's the verdict here?

Also, the dealership told me (and I've read elsewhere) that PCM is recommending 30 hour oil changes for heavily ballasted boats (and possibly using a heavier oil). Seems logical to me, but does anyone else have thoughts on this?

Thanks in advance.

[scott resick]

I too just grabbed a quart of 15W-40 from Walmart and didnt notice it was for diesel engines until I got it home. It says on the bottle "not for diesel engines" I guess it has something to do with the detergent? Looking for an answere here as well.

[scott resick]

I too just grabbed a quart of 15W-40 from Walmart and didnt notice it was for diesel engines until I got it home. It says on the bottle "not for diesel engines" I guess it has something to do with the detergent? Looking for an answere here as well.

**Correction** The bottle says "Not For Gasoline Engines"

[s_kelley2000]

Almost all 15/40 oil is going to marketed as diesel oil but that should be ok to use in your boat and probably what you are looking for. The 15/40 I use says diesel on it but it has not given me any problems yet. Do you have the Excal 343? The Rotella is probably what you are looking for but others with your same engine would know better than me.

Changing the oil in one of these boats is pretty straight forward and easy, especially if you have an oil extractor to speed up the process. But even without an extractor it isn't too bad if you do it after the boat has been used and the oil is warm. Daniel C's write up is pretty good but you can skip the step of pumping it out on the trailer if you don't have an extractor and just let all of it drain out through the drain hose into a container. It may take a while but you can let it drain over night and then change the filter and fill up the next day.

http://www.planetnautique.com/vb3/sh...ght=oil+change

[AirTool]

**Correction** The bottle says "Not For Gasoline Engines"

I've never seen that before on any of the oils. You just need to look for the API Sx rating where the x is generally the latest. I think we are at SM right now but I would have to check. Which oil was that?

[OKWAKEBDR]

So CJ-4/SM is okay? (even though the manual calls for GF-4/SM) I don't know what any of those letters or numbers mean. Is CJ and GF the same thing?

[scott resick]

I've never seen that before on any of the oils. You just need to look for the API Sx rating where the x is generally the latest. I think we are at SM right now but I would have to check. Which oil was that?

After your post I looked at it again. It says do use in gas engines equipped with catylist. But I don't know what that means exactly either.

[AirTool]

Fast...maybe more later.

Cx and Sx are API ratings (American Petroleum Institute) C stands for "compression ignition" (read "Diesel") and S stands for "spark ignition" typically gasoline engines.

The G code is a different organization/society (can't remember the name off hand - and probably European)

Generally, the latest oil is okay (SJ, SM, SN) however:

Engines with flat tappet lifters need an old fashioned oil (obsolete specs) with ZDDP (the zddp was reduced/eliminated in more recent specs to prevent damage to catalytic convertors)

Engines with catalytic convertors need the latest spec suitable for catalyitic converters. I don't remember the spec for that...maybe SJ.

More info available if you have specific questions.

[scott resick]

Fast...maybe more later.

Cx and Sx are API ratings (American Petroleum Institute) C stands for "compression ignition" (read "Diesel") and S stands for "spark ignition" typically gasoline engines.

The G code is a different organization/society (can't remember the name off hand - and probably European)

Generally, the latest oil is okay (SJ, SM, SN) however:

Engines with flat tappet lifters need an old fashioned oil (obsolete specs) with ZDDP (the zddp was reduced/eliminated in more recent specs to prevent damage to catalytic convertors)

Engines with catalytic convertors need the latest spec suitable for catalyitic converters. I don't remember the spec for that...maybe SJ.

More info available if you have specific questions.

Wow. I think I'm more confused and will return the motor craft for something else. Thanks for your effort though.

[Nordicron]

Almost all these engines are either GM or Ford engines used in trucks for everyday duty. I dont see why we just can't run regular old 10w-40 or 5w-30 in the marine versions and be just fine. I know some people have started running mobile 1 5-30 and I'm sure they are just fine too.

[AirTool]

Wow. I think I'm more confused and will return the motor craft for something else. Thanks for your effort though.

The motorcraft is generally fine but if is the synthetic blend, I'd prefer a dino oil like Rotella, Delo, or DelVac. I use the Mobil DelVac.

I do use the motorcraft 5w20 syn blend in both of my new fords....because that's whats specified and I'm confident the syn won't F up the elastomers.

[AirTool]

Almost all these engines are either GM or Ford engines used in trucks for everyday duty. I dont see why we just can't run regular old 10w-40 or 5w-30 in the marine versions and be just fine. I know some people have started running mobile 1 5-30 and I'm sure they are just fine too.

I agree and I really don't understand why PCM went with the 15w40. I know my pressure is quite high on startup (due to cold 15w) but doesn't drop as low as my 99 tahoe 5.7 running 10/30 when the tahoe engine is very hot. Of course my pcm doesn't run nearly as hot.

I would prefer 10/30 in the boat but because the two numbers are closer together and require less modifiers for the multi-viscosity. I'm sure PCM has a reason and it really doesn't make much difference so I've stuck with the recommendation.

[scott resick]

The motorcraft is generally fine but if is the synthetic blend, I'd prefer a dino oil like Rotella, Delo, or DelVac. I use the Mobil DelVac.

I do use the motorcraft 5w20 syn blend in both of my new fords....because that's whats specified and I'm confident the syn won't F up the elastomers.

Elastomers? Know your just showing off. Lol.

[AirTool]

Elastomers? Know your just showing off. Lol.

It's a disease no medication can cure.

[Clibka]

Very impressive as always Tool. I would like to see if someone can just make this simple . . . The first person to post a link to or picture of the correct oil to use in a pcm 343 gets a cookie!!!