Crusader 8.1 eng oil

[jmm48m60]

Good Day Everyone,
Just purchased a 2002 356 aft cabin with crusader engines...looking to change the oil. Many articles on engine oils. I hear the 8.1 has flat cams and needs an oil with special additive (SJ) . Looking to do the correct thing here. What oil is best for that motor.. Engines hours are 550 . Your help is greatly appreciated.

[bud37]

Check your manuals, (hopefully they are still with the boat)...the engine oil recs will be there in the engine sections....I think that you should check that story about the flat tappet lifters though , just to be sure, because roller type lifter assemblies do not require high Zddp numbers.That being said maybe the 8.1 piston ring clearances require something special ( good question, I can't answer).Lots of guys use the shell rotella t 15x40 with no ill effects, and have done for years.One more thing, if the engines have any sort of warranty left somehow, make sure to use the oil that is recommended....

[mjk1040]

I'd check the crusader book too, but I'm a rotella T fan. My Crusaders are 1998 7.4L and call for 40W and thus that's what they get. Then again I know rotella T fans that put 15W40 in everything they own. Rotella T has zinc in it. Mike

[waybomb]

All of my engines get Rotella 15-40.

PV also gets 2 cans of the old GM EOS in each engine each change. This is not the stuff you currently buy in a plastic bottle.

I have many cans left from my drag racing days thankfully The older stuff had lots of zddp in it, much more than the current breed of EOS.

But then there are plenty of folks out there that say zddp is not needed. I ran with that thought until I wiped all three cams one weekend. So now I don't listen to the experts.

[tomschauer]

GM, BMW, Mercedes and others require Mobil 1 for their newer motors. I run that S#*t in everything I own. 15/50 for my GM marine engines.

[mjk1040]

When I bought my Harley, the first oil change after break in, I too went to the synthetic oil in everything, engine, tranny, clutch, etc. One the second oil change the following year I had it all removed and went back to regular oil. With the synthetic oils I heard more engine and tranny noise than I did with the regular 20W50 oil. Not that I don't believe synthetic oils should be better, didn't like what I was hearing. Of course I will run what the manufacture recommends to satisfy the warrantee requirements. My generation was brought up on straight weight oils, you know 30W in the summer and 20W in the winter! When I got out of the garage business after ten years I to went to the synthetics in my vehicles for the longevity between oil changes. Oh then there was the change the oil every 3,000 miles or three months which ever came first. Think the oil and filter manufactures had anything to do with that marketing ploy? You got to wonder is Mobil 1 superior for those engines, or somebody had lunch one day and came up with a marketing plan and picked up the tab? Just food for thought. I guess the only way one would ever truly know would be to take oil sample after oil sample to the lab and see what's what!

[tomschauer]

A friend of mine's father in law is a chemist for exxon mobile. I first met him about 20 years ago. When we started talking classic and performance cars he told me about engines they have running in the lab at various continuous rpms for thousands of hours without oil changes. He says the only thing that will break down mobile1 is excessive heat (400 degree plus). He said you could run it for 200,000 miles, just change the filter and top it off.
Yes, he works for Exxon Mobile, but he wasn't selling me anything, and he uses it in all of his vehicles. I have been using it ever since.

Mercedes and BMW recommend changing Mobile1 every 13,000 miles or once a year for warranty coverage. The last Vette I had required the Mobile1 to be changed every 7500 miles or once a year. So these manufacturers have some faith in it.

With a boat that most of us run only a hundred hours or so a year, you can probably get by with most any decent oil, just a matter of personal choice.

2cents added.

[mjk1040]

I do believe synthetics should be superior lubricants, and knowing a chemist that works with it is a great asset for the case. Personally, as I said when I got out of the garage business, I switched to the 10,000 mile synthetics, and after the first synthetic oil change, I was amazed the oil I was draining looked to be just as clean as when I poured it in. So his statement you could just change the filter and top it off appears to be accurate. If you happen to talk to him again, I wonder about contaminate retention and removal? Just a thought. Great info.

[waybomb]

I use the Rotella in my boat engines.
I use M1 in the cars.
My last Benz had 356,000 miles on the clock when I sold it. It's still running around town. Never smoked.
I changed the oil when FSS prompted me to do so - and was typically around 18,000 miles.
So I did maybe 20 oil changes in 356,000 miles.
And it ran smooth as silk.
Body rusted away.

[Viper]

....I wonder about contaminate retention......

Ya me too Mike. I get the synthetic longevity, but you can't get away from the corrosive combustion by-products accumulated in ANY oil. The longer the oil is left in there the more concentrated these by-products get. The effects (etching) this has on major internal components is noticeable to the naked eye. This is especially bad during the long winter layups. So personally, mineral oil or synthetic, I'm still changing at the end of the season, and if that's the case, longevity isn't a concern to me nor is using mineral oil, the cost however is a concern!