Hydrocruiser

After a lot of study I am back to Mobil-1 too, though I respect Amsoil it's the $ 8.00/qt stuff (Series 2000) that may be a little better. The rest of thier line is not better than Mobil-1. It's not worth the hassle of ordering it and paying freight. Amsoil Severe Duty or Racing does not have an API rating either. Amsoil does not warranty "racing" products in the event of oil failure.

Mobil-1 15W-50 is equal to or better than any synthetic out there.

Redline and Amsoil Series 2000 may have a slight advantage in lower viscosities to Mobil-1 and should for $ 8.00/qt. Probably reserved for those who take thier cars to the drag strip weekly?

Not enough data on Royal Purple to say much except it handles shear well as does Redline and it runs good in my tractor. They may be the best for hard running 4-stroke air-cooled engines. The "moly" seems to help in these applications by reducing friction and heat.

Oh, almost forgot: Outdrive I use only Merc HP. It has antimony in it which cushions gears better than anything and can handle moisture/condensation issues and has been extensively tested and is tried and true. In this case Mercury has probably the best overall product. Tested, reliable and a sophisticated chemistry. Anything else may be a gamble. In this case until Merc says otherwise that's what I am using. Why chance it? I think Merc has a better handle on their drives than they do on their engines in a relative sense.

Oil filter: After my findings why use anything but an A/C Duraguard? For 3 bucks it filters and flows very well and is ranked at the top. The other filters go for $ 10.99 to $ 22.00.

Above all I learned there is no substitute for frequent oil or drive gear fluid changes because of acid formation, water condensation and gas getting into the oil. No filter can get rid of this. Only frequent changes.



Why did I put myself through all this?

R Addiction

I use mercury racing oil filters. But now that you mentioned AC Delco....I work at a GM dealership.....I may have to try them. Anti drain back valve, and I can get them pretty cheap!!!

Shooter

What about Mobile-1 Gear Lube in the drives?

Hydrocruiser

I am sure Mobil-1, Amsoil and RP and all good but Merc HP has been extensively tested and it's synthetic. I am sticking with Merc here.

Chris288

Well, at this point I guess the results speak for themselves... mobil 1 15 - 50 is the clear choice of many..

P.S. I refuse to pay 12.00 for a gallon of regular ol'e Merc. 25-40 dino... There are much better and cheaper choices out there..

Hydrocruiser

Plus even Merc admits they had to "develop" a 25w40 synblend for their hard running 4-stroke outboards. That unto itself says something. Plus they charge $ 4.95/qt which is about a dollar more per quart than Mobil-1 when purchased in bulk.

Lmarth

Hydrocruiser-- I'm probably going to start something with this, but The question I recall Teague addressing in Powerboat a year or so ago (I plan to check my archives) had to do with roller Lifters skating/not rolling over the cam profile with cams running valve springs with low seat pressures. I recall the number being around 125 pounds. The coversation was't definitive, just that rumor had it that the roller lifters may not roll all the time with synthetics. As I said, I'll go back and look for the reference, but I recall disscussing this with a friend of mine who ran a 1200 HP 672 at the time. My humble opinion is that this is one of those urban legends that just won't die (Like broken 500HP valve springs). I apologize in advance if I'm confusing things.--Lou

DENNYB

Kendall Straight 40w and change every 12 hours along with a fram filter.

Hydrocruiser

Maybe I will go back to using kerosene like Henry Ford did in the Model A's.

Lmarth

Hydrocruiser-- Thanks for a quick response. This is obviously an emotional issue. I just found the October 2001 issue of Powerboat where someone asked Teague about running Synthetic motor oil. He indicated that he HEARD some people say that roller lifters would slide but that HE had not seen it. This is not the reference I was looking for. It was about a year ago and as I said, mentioned spring seatpressures. The only reason I poke at this stuff is not to split hairs, but to minimize the mis-information that's out there. We're all trying to do best by our toys and keep others from repeating our mistakes. Time to take a deep breath. I'll continue looking for the article. --Lou