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The Peckish Synapse

Grumpy Bear

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The Peckish Synapse

The truth is a hard thing to find and why, I suppose, it intrigues me. Often confused with facts. Considered opinion by some. Rarely defended and often criticized. But truth, it has power.

I find truth in three areas fairly easy to find; God, math and physics. That is if you go to the source and not the person manipulating them. As the last two are the result of the first….I find ‘it’ reliable. Who can question God?

Isaac Newton is sitting under a tree one day and an apple falls to the ground. He ponders this event and today we see the result of the meditation as the three laws of motion. Does that mean Newton invented Motion Law?

No. It had always existed. Isaac was just the first to understand it well enough to explain it. How? Was God ignorant of that law? Hardly. He created it. So the source is faithful.

Albert Einstein is contemplating a train and the perspectives of various observers. That meditation produced several Theories of Relativity. Theories solid enough to be used to send men to the moon. How?

Galilei Galileo drops two dissimilar balls off a famous leaning tower. Gravity calculations results from his meditation. Did he invent gravity? We still use those equations. Your ECU/PCM can’t operate without them. How?

The thing that connects God’s physical laws to the study of Physics is Math. That is how!  That is in explaining the workings of the natural world. Data is our friend. But only if you understand its significance and, and it’s a big AND, you don’t bend the math to suit your will. Back to Galileo and scientific method.

This the case the first thing people who hate the truth attack is the math. More precisely the measurement. Then the method and then….they just don’t want an answer.

Well I do and am quite content not to use the abstract to muddy the definite to irrelevance. That said I’m not oblivious to it either.

What does that mean? Means I’m not going to apply a rule of measurement intended for measurements in the field of quantum mechanics to cast a doubt about the accuracy of a GPS measured mile in calibrating my odometer. But I also see the need for a large enough sample size to relegate any unintended error in measurement to a decimal so small that it matters not. All I’m looking for is a ‘process capable’ value that can be used to compare one apple to another.

Data will tell the story, not the story teller.

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Data is your Friend


But only if it’s good data.


At any given gas station the delivery to the tank will vary even though it has an automatic shut off tripped by fuel reaching the nozzle. The reasons are various and not the point of this post. Point is it varies. At the same pump, at different pumps. At different stations and so on. How much? From best to worst? If I gave you a number you would question it so I won’t. I’ll use a random number than is well within the range of variance I’ve experienced.  


Let’s call it a quart. Let’s use Pepper as our example. I run about a half tank or 13 gallons between fills. It’s just my practice. On a 325 mile trip that is 25 mpg.


Variance of a quart give a range of =/- 2% or 24.53 to 25.48 mpg.


Let’s say my odometer is also off by 2%. A likely scenario. Could be high or could be low. If we take the worst case in either extreme that is an 8% shift if mpg.


As the tires wear and assuming you run the too minimum that is 1% additional error and the compound error is now 10%. That is fuel variation, odometer error and tire wear compound error total.


As this was done on a percentage bases it will hold for any mileage.


A 15 mpg example gives the range of error 13.5 to 16.5

A 30 mpg example gives the range of error 33.0 to 27.0


Pretty big holes. Now let’s talk ‘other’.


Ripley’s Believe it or Not: Winter/Summer fuel composition variation in BTU content per pound of fuel is @ 2%.

Tire pressures alone can create a 10% shift. 


Weather related variations, which are really viscosity issues, and that number can be huge and can be defined only on a case by case bases. It can only be define statistically. Miami is going to be a different number than Nome.


You have to minimize the noise in the statistics to get that value and that isn’t that hard.


You have to keep records and then you have to analyze that data and if you like me, graph it. I’m a visual learner. But you have to do it over very long terms and track by season and by year.


Now you can spend the next three to five years doing this but you will come to the same conclusions I have. First and foremost is a single number tagged in space on a single tank hand calculated or not is meaningless unless they are giving prizes for best uncorrected single tank values. You don’t buy gas or make choices base on that number if you’re a wise person.




Peppers actual log. Worst tank 22.90 mpg. Best tank 33.3 mpg. That is 45% high to low. Life time number is 27.2 mpg.

The red line is the 36 tank moving average. Ask yourself what one tank means. What a 25 mile DIC number means. This chart represents @ 82K miles of history. Nearly 3 years. 


Chart updated 6/7/2019 1600 hrs. 



Edited by Grumpy Bear
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Data Driven



The correct viscosity is the viscosity the gives the lowest bulk oil temperature for the load it services.

This should be a no brainer. Heat is friction. The right viscosity keeps metal off of metal and at the same time gives the least internal fluid friction that will permit the first. And there is a data driven way to find that value…and…

And this would have continued for about another 300 words (and it did) and it dawned on me after being beaten by some recent absurdity that supplying the data that leads one to that conclusion would just be silly.

If you can put a truck in a wind tunnel and prove that a tonneau cover reduces drag, and you can every time, and physics proves that drag is resistance and a reduction in resistance reduces fuel consumption and that is proven by a hundred years of fluid dynamic study and they still choose to believe a third party vendors observation or a TV series test is the truth; what chance would I have in conveying the sequence that provides a data driven conclusion to something far simpler?

This is what happens when you give people a ‘like’ button and they become convinced that a ‘consumer review’ is the same thing as data.

Now I could become very frustrated with all that but as I sit and sip my morning coffee a smile comes to my face. Hey…this really doesn’t matter does it?  What matters is the result…actually, my result. I’m the one buying the fuel or paying the maintenance bills.  

According to the thumbs up crowd the things I do to get Pepper’s results should not yield its result and yet…..it does……argue with that!

Am I obliged to share the methods or the results? Hardly. Then what need do I have to argue the point? None. State it and move on……

On another matter….I don’t do poly-ticks….(Paintor)

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2 hours ago, Cpl_Punishment said:

I'd be interested to read those 300 words, even though most of it might go right over my head and no one else would appreciate it. 

Data is relative to the Observer.


Nobody drives at the same temperature, elevation, wind speed, or even constantly on a flat road.


Thus data for MPG....is only relative to the Observer.


BTW GrumpyBear, Mythbusters has been proven wrong more than once. For amusement purposes only. 

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11 hours ago, Paintor said:

Data is relative to the Observer.


Nobody drives at the same temperature, elevation, wind speed, or even constantly on a flat road.


Thus data for MPG....is only relative to the Observer.


BTW GrumpyBear, Mythbusters has been proven wrong more than once. For amusement purposes only. 

Velocity and position are relative to the observer (and to the observed). Einstein, correct? But I get your point and as I do I will agree with you agreeing with me the countless number of times I’ve stated that improvement is ‘case by case’ according  to your conditions and HABITS. I’ve advised using percentages instead of absolute values to gauge progress. 1.5 mpg improvement over 15 mpg is the same step value as a 3 mpg over a 30 mpg base.


As far as Myth-Busters; people don’t seem very picky about the sourced of information anymore. If you find an idiot on the internet with a million likes his take will be taken equal to Jesus. How many times have I heard, ‘it is commonly agreed’ as a proof?


Is that how the Lemming story got started? They all commonly agreed?  :rolleyes: I heard so I jumped :thumbs:

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On ‎6‎/‎5‎/‎2019 at 6:22 PM, Cpl_Punishment said:

I'd be interested to read those 300 words, even though most of it might go right over my head and no one else would appreciate it. 

Then I will put something back together and PM you. Your welcome. Give me some time I have to find all the pieces to the that bridge I blew up. :P


                                                                         :thumbs:PM Sent! :thumbs:

Edited by Grumpy Bear
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  • 3 weeks later...

Garbage In, Garbage Out 

Filling station pumps and accuracy. Stopped at a station where a gentlemen was doing the State checks so took the opportunity to ask some. 3 cubic inches under and 6 cubic inches over on a 5 gallon fill is the allowance. They are checked every two years unless someone files a complaint. (There are 231 cubic inches in a gallon)

My average fill is 15 gallons. Half a tank. A legal under fill then is .039 gallons. A legal over fill .078 gallons. .118 gallons possible variance from pump to pump. (.447 liters).

On a 15 gallon fill and 30 mpg I travel 450 miles. If those 450 miles a legal over fill would read only 14.921 or 30.16 mpg. The under fill would read 15.039 thus 29.92 mpg. A spread of 0.24 mpg or 0.79% high to low. Livable but not within 0.1 mpg which some claim as the accuracy of GM’s on board fuel reporting. If my average were say 15 mpg then that error is double percentage wise. My DIC is 7.6% happy.

This is only the first problem with such a claim. The second would be the sample size the claim is based on, a tank or two. The work around is, it was the same pump at the same station. Certainly improves the odds but does not solidify the claim. Most stations have a master pump that feeds multiple dispensing pumps. How many were running at each fill? The issue is line pressure and line pressure goes to fill rate and that to agitation, froth and the effects that has on the auto shut off. Don’t tell me you don’t notice the delivery rate change when the guy on the other side of your pump is topping off.

The real wild card is the frequency of the inspections and how quickly that certification can be out of spec and how long it can go unnoticed by anyone that would complain.

The approach and load. Allot of stations have some pretty steep run off grades. The same pump addressed from opposite sides yields and different possible end point. Some tanks have odd shapes and even fill volume may trap some vapor in one direction it does not in another.

Point is there are allot of variables and yet with careful records, some data mining and statistical analysis over thousands of miles and dozens of tanks and using a single pump of very recent calibration as a touch stone you have a tool to gauge accuracy of every other pump you might use.

If I’m careful and I am I can find the standard deviation of a single pumps delivery and calibrate my OBDII tool to, in my case, that deviation of but .05 gallons. (Use to be a quart before I adopted the 3 click fill) I can add to that the standard legal variance and know that if a fill reads more than .168 gallons different than the OBDII device it is suspect. If I get one that reads 3 to 5 tenths over or under….that’s a pump I don’t use again until I see a new certification sticker. I have a list of such pumps within 100 miles of my home. There are quite a few.

A recent investigative reporter found the percentage of pumps in one state at 16% of all pumps were out of calibration.

So when I hit a pump today that showed a shortage of a half-gallon in 10, the store manager and I had a talk. One that got me some money back and a bag on the pump. It’s not hard to win that argument when there isn’t an unbroken State seal on the pump.

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261F in the pan and he is not worried


Alkylbenzene and Phosphate Esters not used AS motor oil. Polyglycol and PAG are the same thing and while not used AS a motor oil can be used to modify motor oil to improve additive solubility and polarity. 




Note above the end of the yellow CONTINUOUS SERVICE for each and then note below that bearing temperatures are @75 F higher than bulk oil temperatures. Ring temperatures under full load are even higher. Chart is for mineral oil. Bearing reference bottom of the chart. Also note the low pan temperatures that promote long engine life are well below 212 F. 




When different oils are blended the ranges are a compromise of all the oils in the blend. Weakest link. Red Line and AMSOIL are PAO/Ester blends with the esters being the lesser of the two but significant in proportion. You will find their composite continuous temperature to be well below the average of the 'everybody knows' numbers spouted those who scoff at frequent changes, coolers and lower water thermostat settings / lower glycol concentrations.  


You can run Castor Bean Oil in a motor IF you change it frequently enough and keep it cool enough. The question has never been which oil is best or will take the most abuse.


The question is: How much abuse are you going to ask it to take? 


I cool it, clean it and change it often even using the best I can afford to buy. I do not find that wasteful. I find using a really good oil and pulling 9K up a 5 mile 7% grade in 110F weather with the oil running over 260/270 F in the pan and then insisting that once a year changes are okay to be...well….. IMHO of course. 



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  • 3 weeks later...

A book, The Story of Philosophy by Will Durant: The Lives and Opinions of the World’s Greatest Philosophers.


Durant’s astute summation on Aristotle. Quoting a phrase from Aristotle’s Nicomachean Ethics which reads; “these virtues are formed in man by his doing the actions”, Durant’s offers in summation, “…we are what we repeatedly do. Excellence, then is not an act but a habit.”Oddly Aristotle gets credit for something said millenniums after his death, eh?


I smile when I read this and lingered on the phrase, “is not an act”. Why did that bring a smile to my face? Because a single act is exactly what the majority of humanity calls ‘proof’ of anything. Then this is extrapolated into something like, “I’m not speeding $100 dollars on an alignment to get $20 more use out of my tires.


How often I wondered about the people that show photographs of their DIC’s with some really great mpg numbers over very small distances and their ability to give the impression that this snapshot is a fair representation of the landscape of their driving habits. Even more so when willing to go to blows is vain attempts to fain proof in support of such an obvious deceit.


That be as it may it isn’t the intent of this post to nail liars to stakes. It is, in fact, directed at the misconception itself and to offer the truth.


 A single act cannot offer proof thus knowledge to anything that requires a habit to establish.


Guy gets called up from AAA and at his first at bat hits a Grand Slam. Good at bat! If he never bats again his record could read: Batting average 1,000. Hit a Grand Slam at every at bat. While true it is useless in establishing what sort of player, hitter he was. Just a quirk in the ripple of time.


WIKI reports on the MLB rule for Batting Title:


Under current rules, a player must have 3.1 plate appearances (PA) per team game (for a total of 502 over the current 162-game season) to qualify for the batting title.


His habit is the rule of excellence not a single at bat.


Seems everyone but forum people know this. When a fella says he won’t align his truck to save near worn out tires he isn’t commenting on his frugality and insight. That alignment has a profound effect on the next set as well does it not? What he is commenting on is his nature of habit. He sees the movie of his life in single frames divorced one from the other. 


Long life for a vehicle or good fuel efficiency isn’t the result of a single act but the sum of the owners habits over the life of that truck. In fact the habits required to affect excellence at anything both precede and exceed the object.


Improvement is an ongoing process that is never complete.   

Edited by Grumpy Bear
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My wife and I get different overall fuel mileage. She drives and accelerates mostly with the cruise control. I set cruise once I’m at speed. My average is higher usually by a couple miles per gallon. I anticipate red lights and don’t sit and idle. She brakes later and idles more than me.

Sent from my iPhone using Tapatalk

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  • 2 weeks later...

Stuart Chase Quotes. For those who believe, no proof is necessary. For those who don't believe, no proof is possible. 


Attitude is your acceptance of the natural laws, or your rejection of the natural laws. Another Chase quote. 


This guy was a thinker, right? One quote states what you will accept and the other how you will react to it. 


So my question is: What makes men think they have a say? God asked Job (38:33) …..


Do you know the laws governing the heavens,

Or can you impose their authority on the earth?


We can't write the laws of the universe that govern it. We can only observe , record, analyze and hope, perhaps, to understand them. Statistics is a means for analysis that leads to understanding, maybe. But only if we take the time to make unbias observations and keep records. Well...and check our preconceptions and attitudes at the door of reasonableness.


Chase did not give men more authority than they actually have. He offered an explanation for the obviously inexplicable. Human stupidity. 




Edited by Grumpy Bear
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  • 1 month later...

Evil Step-Sister

Ran across Peppers T1 stepsister. Identical save the 3.42 G80 differential. Well and they call it “Red Hot” now instead of Victory Red. A shade under $31K. It was Sunday but it was unlocked so Mrs. and I got an up close and personal sans the test drive.

Took a snap of the window sheet and got a jolt.

16 City, 21 Hwy 17 Mpg overall. Then it showed $2250 a year in fuel cost based on $2.55 per gallon. Some quick math….

That’s 882.35 gallons of fuel. Sticker shows 15,000 miles per year as the reference point so 17 mpg!!

This means the EPA and GM expect that of the 15,000 miles a year you drive that 80% of it will be city and 20%, only 3,000 miles will be highway. I smell fish! I don’t live in downtown Chicago but I don’t live in Montana either. In fact I’m not sure I could get to 16 mpg if I left it idle at Walmart all day. Exaggeration, yes but Com’on man! Why would I give up 62% of my current mpg? Seriously, I would expect the LV1 performs better.

Moving on.

Not quite as ugly as the long bed quads. (IMHO jezz, put the ropes away). I do know where the weight savings came from. The seats! I’ve sat on headstones larger and more comfortable and that isn’t an exaggeration. I’m large but not huge and these things are like the half size chairs I sat in in kindergarten. I thought my 15 was Plain Jane. Yikes! Half of Jane is missing! Wife sat a minute and said, “Those seats are ridiculous. Stadium chairs would be better”. Where is my glove-boxed sized ash tray I used as a glovebox?

Factory steel wheels have gone major “U”-gly. I expect to steer buyers to more expensive versions. Dash seems about 2/3 as deep as the 15’s and has a fall apart if I touch it feeling. That floor covering appears to be a cross between the 15 vinyl matts and some sort of Husky but not removable which makes them useless. That would be a cleaning nightmare. Overall, not impressed. Even less so as the ECU & TCU’s are locked. The only real upgrade from 15 is a backup camera. Woo-who!!

Could we finish the seam sealer? Get a wiring harness the correct length? Put some vinyl chip resistant paint on the bumpers? How about just SOME paint!.



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  • 4 weeks later...

Results that Matter. 




100,000 miles of fuel data. Each individual tank just under 400 miles and just over 14 gallons on average. The red line is the linear trend which represents a 20% increase in fuel efficiency over this three year time period. The bicolored line the lifetime average. 


18 tank running averages in yellow represent about 7K miles per data point. They reflect seasonal shifts. 


Matched to my service records and operating notes I know what the drivers are that elevated the overall result. I know the reason for every outlier. I know when to correct, what to correct and the effect any set number of conditions will have on the result. I know what I can control and what I have no control over. I know when she's sick and when she's happy. 


I know when I read another's shared experience what is likely and what is fishy. What I can use and what to ignore. I know when six tanks is enough for a test and when 36 tanks isn't nearly enough data to prove a point or sell an idea. 


I know that only three people outside myself follow this thread. :crackup:I know it's 4 AM and I'm going back to bed! 

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