Some simple math regarding fuel economy

Probably the long pull up Halloran, the long pull from Barstow to Hesparia, and normal LA traffic.

 

no traffic at midnight. came down 15. across the 10. and up the 110 to santa maria.

thought about doing the bakersfield route. but gps only saved 20 miles. so i stuck with the freeway.

 

Yup.

76,000# on a flat deck.

Calgary AB to Vegas 7.00

Vegas to Orange then empty 35 miles to Fontana and back to Vegas @ 75,000#

6.10

Vegas to Calgary: 6.9

55-60 all the way.

 

The original post, while being generally on the right track, has a serious flaw.

1) It assumes a .4 MPG improvement for a 3 MPH price. Those who test this stuff have concluded that 1 MPH = .1 MPG. But this is only true for sustained driving and does not include or account for acceleration, traffic and the like.
The example is at least 33% optimistic because......

2) the example assumes two very close speeds. 62 vs. 65

My experience with driving at various speeds for sustained periods, is that the slower one drives, the higher or closer the average speed comes to the set speed.

It's easier to average 55 while driving 58 than it is to average 72 driving 75.

The difference between 62 and 65 is really more like 2 MPH over the course of a day and therefore .2 MPG.

3) Slower driving examples always focus on miles driven which really only applies to those who move trailers around, drop n hook and have terminals to work with.

There are a great many others that load and unload their own trailers and often if it doesn't get done by 3 PM Friday, it won't get done until Monday. The $50/ day lost to lesser MPG's is nothing compared to the lost revenue stuck somewhere for 2.5 DAYS.

4) IMO, Fuel economy is only important when expressed as a Cost per Mile or a Percentage of Revenue.

My goal is not to get X.X MPG, average for the month, it is to generate $XXX per day for the month after my fuel bill.

Sometimes I can achieve my goal by driving 58, other times....

 

at least your hitting 6. i'd kill to get that consistently. 95% of the time i'm in the low 5's.

 

I have been playing around with speed for the last year in my 07 Volvo 780 with the D12 engine, 3.58 rears and the 12 speed .78 OD freedomline transmission. What is consistent is that nothing is consistent. It's not as simple as just slowing down from speed a to speed b. There are just way too many variables for one formula to work. The best mpg I got was 9.77 mpg for 265 miles, measured tank fill up so I am not BSing. Sounds great doesn't it?. Well the truth is I was running very light, on relatively flat ground (Walcott IA to Albert Lea MN) and had a tail wind. I was running at 60mph and my rpm's were at 1400. Now because I got that result at that speed and at that rpm, that should work for all situations right? well it doesn't. Put 30k in the trailer and try going from Chicago to Denver. Mpg will tank down to 6.00 mpg. Now raise the rpm to 1500 rpm which gives you 64mph then the mpg will go up to 7+. Lugging down an engine will work when your light and on the flat but will kill the mpg when your running in the reverse situation. The turbo is constantly boosting and that means your sucking fuel.My truck seems to universally get the best mpg at 1510 rpm which is 65mpg. For the last 25,000 miles i have averaged 7.48 mpg and my fuel costs are at $0.48 cpm. I am happy with that performance. The key to better fuel economy is to constantly keep adjusting your driving to the current situation. If you combine as much technology as you can, such as low rolling resistant tires, aerodynamic upgrades, single drive axle etc..you will do nothing but improve your mpg. Mesilla Valley Transport has probably the best fleet mpg average. Just look at their truck set up and you'll see why, plus they do it while running 65 mph. Slowing down is not the magic key to the best mpg for a truck. You must also consider the safety implications when running 55-60 mph in a 70 - 75 mph zone. Traveling at such a reduced speed to the other highway users can be a serious hazard and as a professional driver you have an obligation to drive your truck responsibly. If you are are running significant slower than the other road users and you are involved in an incident that was a direct result of you driving slowly, you could be cited for impairing the flow of traffic. I have come to the conclusion that the best way to better mpg is to improve your overall operation. That means equipment upgrades, buying fuel at the best prices and understanding IFTA, the geographical area of the country you run in, load selection and yes, speed you travel at. But you must remember that everyday is different and all the variables are constantly changing. Above all, if your success and failure is purely based on your truck's mpg then you really should think twice about being an o/o. The cost of fuel is a big number on your P&L statement but above everything is your revenue. If your revenue sucks then slowing down will do nothing. Being a successful o/o is not just about good mpg numbers. It's about the whole package. Mpg is just one of many elements. Customer service is foremost as that is what makes you different to the next guy. Next is your numbers. If you can't manage money then forget about being a success.

 

I've heard O/O's that say they idle all they want, because they are buying the fuel. I finished training a couple of months ago with a trainer that would idle the truck 24/7 if the truck was sitting, no matter the outside temperature. I hated it.

After getting solo for the last couple of months I finally had a chance to get to home terminal and had a review of my performance so far. I have 0% idle time, versus the 33% idle time when with my trainer. The average fuel mileage with my trainer was hovering around 7 mpg in a 2011 Cascadia. My fuel mileage hovers around 8.5 mpg in a 2012 Cascadia. The loads and routes can't be correlated, but I would say about the same between training and running solo. The only big difference is the huge gap between a trainer that had a serious problem with fresh air, and my own complete lack of idling...

.... 1.5 mpg difference.

 

Great job Lepton! Hopefully they reward you. If not have printout made and show it to next Co. when your ready.

 

I do have the printout, with a plot graph and rolling average. The transition is pretty dramatic.

It really makes me go, "Huh?", when I see O/O's idling in a truck stop after spending all that money for skirts, wheel caps, and other aerodynamics... especially if the temperature is in the 50's or 60's and is absolutely perfect for opening the screens and sleeping with peace and quiet and fresh air.

If they are that concerned about fuel mileage that they invest in something in order to get a payback, then it really should be a wake up call to note that eliminating idling can result in a 1.5 mpg increase in fuel savings. There's no up front investment other than maybe some window screens for about $50.

Not idling requires an attitude adjustment and ability to adapt to different temperatures, having warmer blankets or comforter on one hand and putting a couple of beach towels down, getting naked, and sweating on the other hand.

 

A good nights sleep is worth more than fuel, but good for you.

Back in the day, before fuel mileage was even a blip on the radar, I drove for a corporation, and most of the drivers would not shut there truck off all week, unless a receiver/shipper did not like sucking up exhaust fumes and made them.

I would check the weather, and if it was forcast to be above 20 degrees F, I would shut the truck off, and zip the curtain up in that old Corn Binder cabover, and sleep like a baby in my sleeping bag. Well, did this one night, and in the morning when I climbed into the seat to start it, I thought, wow is it cold for 20 degrees. I hit the starter on that old shiny 290 Cummins, and it just went thump..

Well, went inside the small truck stop, and told the guys my dilemma, and they stared laughing and asked me if I knew what the temperature was. It was 13 degrees below zero.....So much for Accurate Weather Forcast....

They said, hey you guys fuel here all the time, so we will put a propane heater on your truck while you go get a shower and some breakfast. Came back and it stated right up, and they did not even charge me a dime....