Danzig, among the 15W40 fleet oils, I’ve used Chevron Delo400 the most with a recent switch to the Schaeffer synthetic (PAO) blend. The synthetic blend allows for slightly easier cold starting and the Schaeffer oil has a more potent additive package. But even the Delo400 seemed to cut down on wear whenever I switched a machine over to it … but that’s merely anecdotal (visual inspection of the drain pan). I have done no lab testing to date. I’m considering doing a lab test on a sample from our Honda 18hp (liquid-cooled, twin-cylinder with a spin-on filter) tractor this fall: approximately 50-60 hours of use over 12-13months. Because of the many months involved, TBN (Total Base Number) testing would be useful to see how well corrosion is being kept in check. Maybe I just need to get a life?
In automotive testing, we’ve seen good results from both Del400 and Pennzoil Long Life 15W40s. Others such as your Rotella, Mobil Delvac, etc … are probably also very good but no gasoline used oil analysis results come to mind. Valvoline has come out with a new fleet oil in a black & blue bottle and has moly (agaion, according to a used oil analysis) but I’ve not been too impressed with anything out of Valvoline’s house and prefer most other brands if given a choice. Motorcraft 15W40 has no moly … but a lot of boron which plays a similar role. Might make a good motorcycle oil for moly-intolerant clutches. Hard to say for sure.
I like Pennzoil’s additive package primarily due to its moly and boron.
Johhny used to be a regular on this site and he works for Pennzoil corporate in Wiscaahnsin. He doesn’t post here as much as he used to. I’d like to think he has been too busy turning laps at Road America in a Formula Ford but the truth is probably something much more domestic and mundane. Occasionally, like El Diablo, he comes out of hiding when his name is spoken.
The subject of 15W40 oils came up in another sub-section of this forum several months ago and
Johnny was bragging about some new shear-resistant viscosity index improver Pennzoil was using. Shell had developed it for them but Pennzoil had exclusive rights to it …. Shell couldn’t even use it in their Rotella oil. He was crowing about taking accounts away from other competitors … Schaeffer included.
So why is the Pennzoil Long Life cheaper? I have no idea. In most stores, Delo400, Rotella and Mobil Delvac are all priced within a few pennies of each other per quart. Then along comes Pennzoil for $0.25 less. Go figure. So much of an oil's cost is marketing and distribution.
“Now I was not aware that Rotella did not have moly but on the other hand I haven’t had any engine trouble with non-moly oil either.”
Keep in mind that we have seen more oil formulation changes in the past two years than in the previous decade. Just when we think we have a handle on a given brand’s formulation(s), they update/change it. Lately this has been more and more companies adding at least
some molybdenum to their oils when 2 years ago it was very rare. As for actual trouble with a brand of modern oil, that’s unlikely with frequent changes of
any oil … but you did say you have worn out motors before which makes your circumstances “special” and worthy of greater attention than most lawn & garden applications.
Interesting on the factory bypass filtration of the Dixie Choppers. But that’d be a bigger waste for you than running a premium (read: $5-$8 per qt.) synthetic oil. Bypass filtration only makes sense if you are running seriously extended drain intervals but your stable of iron gets fresh oil weekly. Still, it’s interesting to see that someone thinks it’s worth the trouble. I still think it would pay off for manufacturers to spend more time and attention on air filtration … especially with all the dust mower decks kick up. Maybe an over-sized airbox covered in a multiple-layer foam pre-cleaner with different densities of oiled foam?
“I’m sure the moly will hold up at air-cooled engine temps.”
It should. Moly doesn’t even come into play until parts of the engine get really hot … like 300F+. Then it is pulled out of suspension and bonds/plates to the hot metal parts of the motor where wear is the biggest problem. An air-cooled engine is an application which seems almost tailor made for a high-moly oil ... or the other way around.
If you do any testing of used oil samples, please post them here. I think that’s the only way to be sure if you’re getting enhanced wear protection.
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Bror Jace
