Mobil 1 Synthetic Oil

The previous owner of my 97 PS190 LT1 used only Mobil 1 Synthetic Oil. Is there a specific grade of Mobil 1 synthetic designed for Marine engines? Most of the retail stores carry 5W-30 and 10W-30. What weight should I be using? Thank you.

[Smitty]

As a Mobil distributor I can tell you that the previous owner made a wise decision on oil but a poor decision on vicosity. Marine engines run much warmer and at higher RPM's than car engines. Therefore you need an oil with a higher vicosity. My recommendation is Mobil 1 15W-50. This will provide excellent protection especially on those hot summer days when you are out skiing or boating all afternoon. If you go to Autozone or Pep Boys, or most other auto parts stores, you should find Mobil 1 oil filters. They pick up 95% more dirt and particulates than standard oil filters. My Dad's '84 American Skier has been running on Mobil 1 15W-50 for 20 years now and it still runs like new. It even provided excellent protection when our impellars when out twice and overheated the engine. No damage was done. You can't go wrong with Mobil 1.

[Prostar19]

The owenrs manual on my 1996 LT1 called for 10w50. I used used 15w50 while I had it.

[Prostar19]

The owners manual on my 1996 LT1 called for 10w50. I used used 15w50 while I had it.

[Smitty]

Not to disrespect that last comment, but Mobil 1 does not make a 10W-40 synthetic. They did however just come out with a new Truck/SUV formula 5W-40. This might be a better alternative to the 10W-40 if your owners manual requests that. A lesson on oil: Must peopel assume that the "W" in the formula means "Weight." Not true! The "W" stands for "Winter." Meaning that the first number represents cold temp. protection while the second number represents hot temp. protection. Seeing that you live in Florida, it is unlikely that you will be skiing or boating in 40 degree temps. Therefore you need an oil with hot temp. protection. The higher the second number the greater the protection against warm temps. Again, I would recommend the 15W-50. I know the owners manual on my 2001 Maristar recommends 20W-40, but Mobil does not make that in synthetic formula.

[east tx skier]

I'm, by no means, an expert on oil. Furthermore, I have a different engine on my boat than was referenced in the question.

That being said, I called Indmar at the begining of the summer. For my boat, they recommend 15W40. They recommended Penzoil, but that may just be who they have a deal with these days. My manual recommends Mobil 1 SAE30. As I understand it, either MC or Indmar used to have an arrangement with Mobil 1, and use of Mobil 1 had something to do with the engine warranty. Just a little trivia. I've seen nothing to believe anything but that Mobil 1 is a fine brand.

Smitty, I am not sure what grade of Mobil 1 synthetic the previous customer used. That is why I asked the question. Are the 20w-40 and 50 grades you recommend synthetic?


Sorry Smitty, I meant to say 15W-50!

[captkidd]

Smitty, thanks for the good info. However, you guys are confusing the heck out of me. You keep referring to numbers that scubat didn't use, so I'm not sure what's going on? (hey, where's the little scratchy-head guy?)

[mastercraft1995]

Smitty I have question about mobil one also. This is just a question so don't take it wrong. I change my oil every 50 hours or less for that matter. I use Pennzoil 20w-50 when I change it. Since I change it so often would I get the benefit of using Mobil 1 15w-50. I've heard nothing but good stuff about Mobil 1, period. I just don't know if I need it since I change my oil so often.

On a side note. I have a 04 Ford Powerstroke have you heard of any issues with people using Mobil 1. If not what weight woud you recommend and how often would you change it? I currentlly use the new Delo 15w-40 oil and change my oil every 3k.

Thanks

Just my experience. I have always used Mobil on both my cars, a Jeep Cherokee and a BMW 3 series. About 2 years ago I started using synthetic on the Jeep and within about 6 months, it developed a nasty leak from the rear main bearing. I went back to standard and the leak slowed almost to a stop. I then read on a BMW forum that some of the owners experienced similar seeping with synthetics. I'm still using Mobil, but standard.