For some reason my fuel economy jumped about 3 mpg this last tank.  Any ideas why?  I've done nothing to warrant the jump. Different fuel blend, hot weather? Been buying my fuel from the same location.

My Toyota  gasser  (22re engine)   is  getting    way better   this summer too...  about  3-4  better.

 

better  summer fuel,    warm weather means   everything turns  easier, quicker.     gear boxes,  tires,   everything   gets  up-to-temp faster.

 

I'm sure Mike will chime in too with his   'warm weather'  equals  better   engine efficiency ..      

.........I'll stick  with my opening  statement about the  rolling friction  on   cold stiff  tires, bearings, trans...

 

Then again,  sometimes,  just sometimes....    every trip is  'with the wind'!    Most of the time, for me,   I am  bucking into  it!

Multiple trips to work. Same route each week. 8 days rather than 6. Can't blame it on terrain or wind, unless I got real lucky and had favored wind each direction all week. Temps in the high 80's and low 90's all week. Warmer than usual. 70's this week.

Is this a peek into what a high idle/fooler would do for me?

Edited July 21, 201410 yr by joecool911

Was your last tank lower than average? Some pumps may "overfill" which lower one tanks economy and raises the next.

Is this a peek into what a high idle/fooler would do for me?

Well,    that is  what Moparman  claims...  pretty  vehemently  too..     I still   maintain there are  much simpler  reasons  for  better summer time  economy. 

Kind of embarrassed here. I was going off my gauge. When I filled up it took 33 gallons. Still up in mileage, but not as much as reported. The distressing thing is that my gauge still read a bit higher than when it would typically set off the low fuel light and tone. So now I'm kinda confused about what would cause the gauge to read higher than normal. Normally the low fuel light comes on at about 29-30 gallons.

Ok...

 

From what I've been playing with I've found there is a roughly 2 MPG gain with two cycle oil vs. without two cycle oil (128:1 ratio). Running colder IAT's on a 24V tend to start losing roughly 1 MPG for every -10*F from 100 IAT temperature. I typically see better MPG numbers in the hot afternoon temps at 100-105*F than in the morning at 50-55*F. Yes. I've got the best of both world cold morning starts and baking heat afternoons. Another odd one that I found about two cycle oil, without two cycle oil in the fuel it will smoke more than with two cycle oil where it barely even smokes.

 

Just tidbits from my daily drive back and forth to work and odd jobs...

Unless your like me and it seems like no matter what you do, your always sitting at the same MPG.

Seems like doing the 6-speed swap is helping me some. I'm letting the truck coast between shifts. The throws are alot longer & the H patterns are wider than I'm used to for right now, so I'm shifting a bit on the conservative side.

Change is good,

Dave

Temp of fuel is very important , all fuel shipped from a pipeline is temp adjusted to 60 degree F

This noted , if fuel is less then 60F on a 100 degree summer day fuel will expand , adding to the volume of fuel available.

I have a fuel sending unit that's going out...my current diagnosis. Need to hook up with Jag1 and look over his tank unit access port through the bed. I don't believe I actually gained mpg's. Sorry to excite you guys.

Ok...

 

From what I've been playing with I've found there is a roughly 2 MPG gain with two cycle oil vs. without two cycle oil (128:1 ratio). Running colder IAT's on a 24V tend to start losing roughly 1 MPG for every -10*F from 100 IAT temperature. I typically see better MPG numbers in the hot afternoon temps at 100-105*F than in the morning at 50-55*F. Yes. I've got the best of both world cold morning starts and baking heat afternoons. Another odd one that I found about two cycle oil, without two cycle oil in the fuel it will smoke more than with two cycle oil where it barely even smokes.

 

Just tidbits from my daily drive back and forth to work and odd jobs...

I wonder if the low smoke feature in the 2-cycle oil slows the smoking?

This is what I think, anyone wants to buy a truck for mpg needs to be slapped, I got a little car I drive daily and I don't like it but I do it. It saves me enough money to spent on my truck. And most of time I use my truck as a truck. I'm not saying getting better mpg out of it doesn't make since, just saying buying big *** diesel and expecting Prius mpg is silly. Not trying to start a war but just an opinion. I might be off subject.

Edited December 7, 201410 yr by Dieselfuture

 

I like using this little spreadsheet it works awesome to figure out which vehicle is cheaper to drive. I just plug in the MPG and fuel prices and it figures out which vehicle is the cheapest for the job. Towing or empty. Like with today prices the 1996 Dodge Ram is cheaper to drive with current MPG numbers used.

 

 

This is what I think, anyone wants to buy a truck for mpg needs to be slapped, I got a little car I drive daily and I don't like it but I do it. It saves me enough money to spent on my truck. And most of time I use my truck as a truck. I'm not saying getting better mpg out of it doesn't make since, just saying buying big *** diesel and expecting Prius mpg is silly. Not trying to start a war but just an opinion. I might be off subject.

 

True^^^ 

30 years ago..   there was a lot less  'pickups'   around..    less people too!   about  100 million less.    

We (people)  are a  funny  breed.        4 door   pickups   buzz  by me  all day long.   with ONE  person inside,  empty.   Unfortunately,   1 vehicle is  all  some of us can afford.. 

I APPLAUD  anyone  doing little things  that  help  with their   economy.   1 or 2 here and there,  it  helps.     But   physics are physics.    a  'working engine'  ie;   loaded, high speed, etc  is  going to use  'x' amount of  fuel.     industry standard is     ~ 4.5  gallons  per hour  per  100 hp.   *2.4 gph= 25 mpg's @ 60 mph=  ~ 60 hp for  us.

 

Prius  needs  what?    14  hp    (or some ridiculous number)     to  maintain   55 mph?     

 

Do we  'need'  4-600 (or more)  hp?   hell no.   But man,  it sure  FEELS  GOOD!      Not using it,  that is  the trick!

So to the OP about him gauging MPG off his gauge..  The gauge is weird.  If I am on a long trip the gauge will hardly move, basically showing better mpg than actual.  In the city, the constant sloshing drops the gauge to under actual MPG.  The gauge is very slow to respond, even when I had the sending unit out and played around with it, it would take forever to change.  To me, it is just a general reference...   The low fuel light seems slightly more accurate but can obviously be off as well.  

 

Hand recorded pump fillups are the only accurate way to do it.  Not with the overhead, not with the scangauge, do it all by hand.  

 

As for Hex getting the same mileage all the time, I am the same way.  I think you, like me, drive very consistently.  You don't floor it one day and drive like granny the next.  I got a consistent 21-23 when I drove my truck no matter what I did.  To get up into the 25+ range I had to take off slowly and drive slowly (55mph).  I had one freak tank (musta had a tailwind) that netted 24mpg at 80mph from new york back to missouri.  Wind goes west to east though so I'm not sure what the deal was.  

ISX conditions yo can do such with fairly consistent MPG's. Now here I can driver back and forth to work and the next day drive to McCall Idaho and alter the MPG number. Or have to climb a 16% grade to get to the fire chief's place, or maybe haul a load of firewood. That why my numbers are very dynamic and extremely difficult to get a consistent number. Heck I might have a summer where I get called out several fire call than be caning the throttle around other vehicles.

Know what you mean Michael!

I too have cooler mornings and hot afternoons. I do get better gpm's when the iat's above 100 degrees. But the biggest mpg jump is how I drive. I have a 6 speed. These trucks have a lot of power and it's very tempting to to drive like I'm in a race. I have to remember my trucks is built to tow anything with all that power. If I shift at 1500 rpms and keep it at under 65, 55 is best, I get great gpm average but not high outrageous numbers like some report I think they are lying. I have a scan gauge II that I use.

I've only reach 27.2 MPG once. But typically I see...

 

• 16-18 MPG @ 65 MPH
• 19-21 MPG @ 60 MPH
• 22-24 MPG @ 55 MPH

Now towing the RV...

• 11-12 MPG @ 60 MPH
• 12-14 MPG @ 55 MPH

I need the protection of my big heavy truck with the way people drive crazy around here. Besides I tried the 2 stroke in my wifes Subaru and it didn't work so hot