Way too many things change from tank to tank to call anyone's short-term observations clinically relevant. Period.
First, I'm confused by your comments. You stated that you blended T6 (1/3) into T5 (2/3). But you also stated you went from a 20 grade to a 40 grade. Which is it? And what HDEO did you move from that is a 20 grade anyway? Your comments are contradictory and leading me, well, I don't know where ...
Plus, your math is, well, poor. You start at a claimed 16mpg, and then state a "13%" increase is = 18.5? Nope, that's a 15.5% increase. Perhaps you fat-fingered the calculator? I must confess that sloppy work does not instill confidence in me. Sure - we all make mistakes. I, too, am flawed and make mistakes. But your math and claims don't match up.
And to be honest, I'd like to know just how "light" this 5ver really is? I pull an RV too; I've NEVER seen that kind of mileage at a "normal" speeds when pulling a wind-brick. You're telling me you can average 18.5 mpg pulling a 5ver? I find that incredulously hard to believe. What does that make your empty and unloaded mpg???
You mention the term "statistically significant". I seriously doubt you really know what those words mean to a statistical process quality control engineer. That's what I do for a living.
I noticed once that Schaeffer's claimed something like a 7% fuel economy increase by switching to their syn products. I found that pretty heady, so I contacted them and asked for details. They were very forthcoming and sent me the actual study resutls. What they were talking about was running big-rigs with conventional lubes switched to syn lubes. But it was ALL lubes, not just the engine. They switched to syn engine oil, tranny fluid, diff fluid, etc. The cumulative total was about 7% gain in an "on track" verification run. It was not fleet data. I cannot find my archive of it, but I recall it was run to some ISO or ASME test protocol. The data seemed legit to me. But again, it was a major gain by switching ALL lubes to syn, and it was well less than double-digit percent increase.
But now Reg# 43897 claims "several" mpg gain? Presuming he was averaging 15mpg (it's a guess on my part, and very reasonable estimate) before his grade shift, and then he suddenly went to 18 mpg (3 mpg would qualify as "several" where I come from), that would be a 20% increase! TWENTY percent! Schaeffers could only pull out 7% by swithcing ALL lubes to syn, and I'm supposed to believe that you pull out a 20% increase by making some hybrid from a blend of T5 and T6?
I'm not saying you're a liar; that would be rude and I'd have to know a lot more about you to make such a bold claim; I won't do that. But what I'm saying is that while I agree you may have experienced a shift in economy, there are a whole host of things that you're probably not tracking or aware of that play into all the variables of fuel economy.
Not for one moment in a sliver of time do I think you gained "several" mpg by making your 40 grade become a 33.333333 grade. Not at all. It it were that easy, to gain a presumed 20%, then everyone would be doing it. It would be common knowledge, but it's not.
For reference, look at the Schaeffer data:
http://www.schaefferoil.com/supreme-7000-engine-oil.html
for their 7000 series; "results available upon request"
3-5% claimed gain; cartainly not 20%
Here is what Castrol claims going from 15w-40 dino to 5w-30 PAO:
http://www.castrol.com/castrol/sectiongenericarticle.do?categoryId=9045281&contentId=7079765
4% gain; that's what they claim in real controlled testing.
And those statements are always the " ... up to ..." or some other form of "best case" statements.
I don't know where Fredericton is; I presume it's in Canada? That's the only place I could find with such a referece. I'd have to know something about your environment and operations to see what may be contributing factors.
I don't doubt you are getting more mpg; I doubt your garage brew was the sole cause.
You indicate that you've read my posts and you're familiar with my mantra. OK - fine. Then you'll also know and be able to acknowledge that I'm all about factual data and not rhetoric. I not only want to know the end result, but the contributing conditions to that result. Too many times there are underlying variables that are not known or controlled, and people presume things they should not, which leads to poor conclusions.
Again - I'm not calling you a liar; I have no cause to believe you are. And I will publically apologize here if that's the offense you took. But I'm also not accepting that you got "several" mpg gain by putting in some T5 with your T6 as sole causation.
