improving fuel milage

riverrat2000

Seasoned Expediter
I have been trying different things over the past year to increase fuel milege and though I would share
the results To start with I have a f-112 century class straight truck,with a pusher axle
I have installed a black rock APU on it and have to say that I am very pleased with it after 2000 hours
and no problems, in the past I have had a pro heat which was ok, one from executive air that was just an expensive anchor and one that I had put together myself. I think the blackrock is the best for my application.
Now to the fuel improvements, the baseline was 9.02 mpg by the computer and after 1000 gallons of fuel was used
Now this one is a suprise I added a harvard bypass filter not to save fuel but for reduced maintenance costs but noticed that I started getting around 2 tenths a mile better fuel.
When the tires needed replaced I switched from goodyear to top of the line michelins and that added an increase of 3 tenths.
I also added motorcote to the oil and after a while it seemed to add a tenth or two to the milage.
Then along came ultra low sulphur fuel which I seemed to lose a few tenth too so I started
experimenting with different fuel additives always trying it for at least a 1000 gallons, all of them seemed to work at least a little bit but then I tried Howes diesel treat and wow thats the one that worked for me and it ain’t near as expensive as most of the others.
Today as I write this the computer is showing 10.19 mpg for a boost of1.17 mpg.
My next project is to add airtabs to the truck and see if they are worth the $200 buucks they want for them, time will tell
So anyone else have some hints or suggestions, my goal is to break 11 mpg
 

Turtle

Administrator
Staff member
Retired Expediter
I'm a Howes fan, too. I can see a definite difference in tank fulls with and without it having been added. It's pretty amazing, really.

Nitrogen
Replace the air in your tires with nitrogen. It'll save your tires, and you, from unnecessary wear and tear. Nitrogen seeps through the rubber and leaks out just like the oxygen in compressed air does, but the nitrogen molecule is much larger than an oxygen molecule, so it leaks out at a much slower rate.

The typical auto or truck tire filled with compressed air will lose about 2.7 pounds of pressure per month. Same tire filled with nitrogen will lose .7 psi, or less, per month.

The result is, the tires stay properly inflated longer, and a properly inflated tire, regardless of whether it's inflated with air or nitrogen, will run cooler, because of less tire surface area meeting the road, and will take less energy to roll that tire over the road. You'll get an average increase of 25% more tread wear, and somewhere between 3% and 5% better fuel mileage. Nitrogen will also run smoother, and give you better handling. And you quite honestly don't have to deal with daily or weekly psi checks when the tires are all hopped up on nitrogen.

On my Sprinter I see a 1.2 - 1.6 pound loss per tire about every 20,000 miles. They should be rotated more often that I do, probably every 7500 miles or so, but unless you have an alignment problem or are seeing uneven wear from another cause, the main thing is to rotate them evenly over time. Don't rotate them at 20,000 miles, then again after 8,000, then again after 10,000, stuff like that. I've been rotating mine every 20,000 miles, with even tread wear all around. These are 80,000 Michelin's and they currently have 95,000 miles on them, and we (me and my tire guy) estimate that I'll need to replace them somewhere around the 110,000 mile mark (when the tires hit the 4/32 tread depth). At 100,000 miles that would be a 25% increase in tread wear, and at 110,000 miles it'll be a 37% increase. That's pretty significant considering it's almost solely due to keeping them properly inflated day in and day out, simply by using nitrogen. My spare is inflated with nitrogen, as well.

I paid $5 a tire to have them inflated with nitrogen, and pay the same each time I have them rotated. Because I run different tire pressures on front and rear tires (55/80) I can't just have them rotated just any ol' place, it must be a place where they can bring the tires back up to pressure with nitrogen.

Of course, if the tires are low and need to be inflated a little, if you can't find any nitrogen handy, regular compressed air works fine, and it can always be deflated and re-inflated with nitrogen later.

Most places charge between $2 and $5 per tire for cars and vans. $5 is a good price, $10 is a little on the high side, but not overly so. Anyone that wants to charge you more than that, walk. Not sure what the pricing for truck tires would be. I would guess somewhere around $10 per. Incidentally, tires that have had the life run out of them under nitrogen make much better candidates for retreading.

Someone who doodles around in their Camry and puts 10,000 miles a year on their cars may or may not see much of an improvement with nitrogen, but people in trucking can see dramatic improvements in tread wear and fuel mileage when nitrogen is used. If it's good enough for NASCAR and the Space Shuttle, it's good enough for me. Plus, nitrogen is almost the standard in Europe, and elsewhere, anymore. Many more gas stations in Europe have nitrogen tanks rather than air compressors for the customer's tires.

Most big tire dealers have nitrogen, and if they don't they'll know who in town has it. I think most Costco's have it now, in US and Canada, and I heard Pep Boys was in the process of having it installed in their service locations. Tire Discounters in the Cincinnati area has it. Tire Warehouse, Dunn Tire. Only about 20% of tire dealers have it, but most of the big ones, do.

The whole nitrogen hype sounds like, well, hype. And for years I thought it was. But it's not. If you have a truck tire that normally lasts 270,000 miles when filled with air, it will last 337,500 miles if filled with nitrogen. Now you're looking at a cost savings of $120-$150 per tire. That's serious money, especially for a fleet owner.
 

greg334

Veteran Expediter
Computer?

Are you using a CAN adapter and using a program or are you using the trucks computer?

When you get your tires, check the diameter of the tire against your originals. I know that there is some adjustment that can be done to the ECM to adjust to the tires if they are different diameter - make sense?
 

riverrat2000

Seasoned Expediter
actually I am using the truck computer but I also have gps that shows me how fast I am going and the truck speedometer and the gps match so it should be accurate. The nitrogen idea is an idea that I had looked in too some time ago but forgot about now that i have been reminded of it I am going to give it a try when I get home,thanks also thought of a batman hook to latch onto a J.B. trucks icc bumper that is going the same way might take longer to get there but the fuel mileage should be out of this world, lol
 

unorthodoxneon

Expert Expediter
Also about nitrogen that i dont think was mentioned is that nitrogen doesnt fluxuate in pressure like air does. When air gets hot it expands and vice versa. Nitrogen will keep close to the same pressure no matter what the temp is. Paintball players will know what i'm talking about :+
 

geo

Veteran Expediter
Charter Member
Retired Expediter
US Navy
i use ace II and yesterday filled up and was suprise that mpg came out to 34 miles, most times it around 25 to 28 mpg
in a sprinter that's not bad
just watching the foot on the pedal saves alot and running to redlights and not racing to them helps to
 

Turtle

Administrator
Staff member
Retired Expediter
http://www.cleanmpg.com/

Cutting edge information on what's out there, what's coming, and seriously serious tips on hypermiling.

Hypermilers, by definition, are those who get better fuel economy than the EPA's highly distorted figures you see on the stickers of new cars. Most hypermilers drive hybrids, but many of their techniques apply to non-hybrids, as well. Techniques like slower starts instead of jackrabbit starts, coasting to red light in order to catch them on green, drafting on the Interstate (close-in drafing, a la NASCAR, isn't really recommended, but long distance drafting works rather well), and getting rid of any extra weight and anything that can cause additional wind resistance. Some go as far as to remove luggage racks, passenger seats, you name it.

Maintenance is one of the most important things that can affect mileage. Half a quart low makes the engine work juuuust a little harder, which can result in a .3 or .4 percent hit on fuel mileage. OK, so .3 percent isn't very much. If you normally get 20 MPG, a .3% hit is gonna get you 19.994 MPG. But it adds up. 100,000 miles divided by 20 MPG is 5000 gallons. Divided by 19.994 and it's 5001.5 gallons. OK, so that's still not very much. But you'll take another .4 percent hit for each 1 psi your tires are under inflated. The wrong oil weight and it's another .2 or .3 percent. Dirty oil and it's another .2 or .3. Out-of-balance or alignment tires and it's another hit. A dirty truck takes a hit. All these little points here and there quickly add up to 2%, 3%, more. Airtabs are gonna help, I think. :)

With expediters, weight can play a big part. Those who have been at it a while, especially in the same vehicle, can start accumulating all sorts of this or that. I'm extremely guilty of that. If I might need it, I want it in the van with me at all times. I carry a George Costanza winter coat (think Michelin Man) with me even in the summer, cause ya never know. I might go out in June, and not come back home until September, and I might just get sent to the top of some mountain in Montana the week before I go home. I carry probably 150 pounds of tools with me cause I might need them. Might, might, might. If you can part with it, even for a part of the year, it'll help your fuel mileage. Tire chains 24/7/365? I dunno.
 

davebeckym

Expert Expediter
RE: improving fuel mileage

The Nitrogen is free with tire purchase at Belle Tires in Michigan. Don't know if they're in any other states.
 

greg334

Veteran Expediter
RE: improving fuel mileage

Turtle,
Thanks for the link, this is funny because there is a group in Ann Arbor who works for the EPA and they are putting together a site that is somewhat like the one you gave the link to. The difference I think will be that they will be posting a lot of their information – as soon as I get an email from them with their link I will post it.

But

I found this list on the web site for Hypermiler –

* Do not use quick accelerations or brake heavily: This reduces fuel economy by as much as 33 percent at highway speeds and 5 percent around town. EPA tests do not account for this kind of vigorous driving.

I agree with this, but in traffic like LA or Chicago – what’s the use you either have to accelerate hard to get out of the way so you don’t get hit or slam on the brakes to prevent slamming into the car/truck in front of you.

* Do not idle excessively: Decreases average FE. The EPA city test includes idling, but drivers that experience more idling experience lower MPG.

This is a no brainer, but for some of us have no choice.

* Do not drive at higher speeds: This increases aerodynamic drag (wind resistance) and mechanical friction which reduces fuel economy. The EPA test accounts for aerodynamic drag up to highway speeds of 60 mph, but drivers often exceed this speed.

OK please guys don’t drive at 45 or 50MPH like many do to save a gallon, it is dangerous with everyone trying to pass you on a two lane highway – if you have to drive at 50 MPH or even 60 MPH in a 70 MPH zone, you should just stay home.

* Cold weather and frequent short trips reduce fuel economy, since your engine doesn't operate efficiently until it is warmed up. In colder weather, it takes longer for your engine to warm, and on short trips, your vehicle operates a smaller percentage of time at the desired temperature. Note: Letting your car idle to warm-up doesn't help your fuel economy, it actually uses more fuel and creates more pollution. Drive to your furthest destination first and then as you are heading home, stop at the closer destinations in order from furthest to closest as the car is warmed up for longer portions of your drive.

Cold weather is being solved by global warming, so cold weather operations should be solved within the next twenty years.

* Remove Cargo or cargo racks: Cargo and/or racks on top of your vehicle (e.g., cargo boxes, canoes, etc.) increase aerodynamic drag and lower FE. Vehicles are not tested with additional cargo on the exterior.

Sorry but cargo racks and roof racks are designed by the car manufactures to be integrated into the car’s design. And yes they are tested (per GM) with luggage on the racks during one stage of design but the EPA’s luggage is at the airport being inspected by the Department of Homeland Security.

* Do not tow unless absolutely necessary: Towing a trailer or carrying excessive weight does decrease fuel economy. Vehicles are assumed to carry three hundred pounds of passengers and cargo in the EPA test cycles.

Duh! How many of you tow a trailer behind your little car all the time?

* Minimize running mechanical and electrical accessories: Running mechanical and electrical accessories (e.g., air conditioner) decreases fuel economy. Operating the air conditioner on "Max" can reduce MPG by roughly 5-25% compared to not using it.

Most A/C units are overkill and setting it at a level that is comfortable for the passengers has an advantage over setting it at the max. On the other hand, traveling through the desert yesterday, my A/C was on MAX and the cab (not the sleeper) temp was still over 95. The heat from the aluminum ring at the base of the shifter was over 105 according to my laser thermometer.

* Avoid driving on hilly or mountainous terrain if possible: Driving hilly or mountainous terrain or on unpaved roads reduces fuel economy most of the time. The EPA test assumes vehicles operate over flat ground.

Another Duh! I tried to avoid the Rockies to get 8 MPG but I just could not. Actually I am told that they do testing on the road around Ann Arbor – nothing flat there.

* Do not use 4-wheel drive if it is not needed. 4-Wheel drive reduces fuel economy. Four-wheel drive vehicles are tested in 2-wheel drive. Engaging all four wheels makes the engine work harder and increases crankcase losses.

A third Duh! Don’t sell cars/trucks with 4WD would solve the problem. I am trying to figure out the crankcase lose they speak of.

Maintain your Automobile: A poorly tuned engine burns more fuel, so fuel economy will suffer if it is not in tune. Improperly aligned or under inflated tires can lower fuel economy, as can a dirty air filter or brake drag.

This is the most important thing you can tell someone. Too many times people are just ignorant of how to check the tires or oil. The other day at Wal-Mart there was a lady who was just so ignorant about her tires, she was replacing her tires because they were low on air – no sh*t! The manager and the mechanic were trying to tell her that the tires needed air, not replacing but the customer wins – the manager told me the tires only have 8000 miles on them. Again I repeat that every driver’s license test should have mechanic based questions in the test and a demonstration of the basic skills of tire checking, oil checking and other things.

Try and purchase high BTU content gasoline if available: Fuels Vary in Energy Content and some fuels contain less energy than others. Using oxygenated fuels or reformulated gasoline (RFG), can cause a small decrease (1-3%) in fuel economy. In addition, the energy content of gasoline varies from season to season. Typical summer conventional gasoline contains about 1.7% more energy than typical winter conventional gasoline.

Ok I wish they would publish a list of gasoline that has high BTU content and where to buy it. Outside of Av Gas, I think that this is a stretch in many markets and avoiding oxygenated fuels or reformulated gasoline may be impossible, I mean you may burn up 10 gallons a month going to a station to buy non-oxygenated fuels or non-reformulated gasoline.

Inherent Variations in Vehicles: Small variations in the way vehicles are manufactured and assembled can cause MPG variations among vehicles of the same make and model. Usually, differences are small, but a few drivers will see a marked deviation from the EPA estimates.

One trick I found out is the manufactures do not just pull a vehicle off the line and give it to the EPA for testing, they go through it before it is handed to the EPA to make sure that it gets the best mileage possible. But how can you determine if your vehicle has some variations that will affect mileage?

Engine Break-In: New vehicles will not obtain their optimal fuel economy until the engine has broken in. This may take 3-5 thousand miles.

Again this is the second best advice you can give someone.

Thanks again for the link Turtle.
 

geo

Veteran Expediter
Charter Member
Retired Expediter
US Navy
RE: improving fuel mileage

check with 3 people when it comes to maintance and they all said
it is a good idea to use nitrogen in tires
so now working on find a place in area that does it and for how much
 

terryandrene

Veteran Expediter
Safety & Compliance
US Coast Guard
RE: improving fuel mileage

I use COSTCO for all my tire purchases. There one-price-out-the-door policy makes price comparisons easier. When on layover, I seek out a COSTCO for a free rotate and balance every few thousand miles. Most if not all now use nitrogen only at no extra cost. I have gotten 180,000 miles on a set of Michelins with pressures of 60/80.

I also think it's pretty important to keep good shocks, particularly on the front and have an alignment where the adjustments are made to compensate for the average operating weights of a van.
 

nightcreacher

Veteran Expediter
you want to save money?slow down,not only saves fuel but wear and tear,,thats from tires to belts,for those that dont like to check tires,nitrogen is great as it leaks out at much slower rate,also does not expand and contract like tires with air,in any event,tire pressures are a must for good fuel economy,keep those injectors clean too,1 fuel filter full of automatic transmission oil will do the trick,on the worst clogged injector,ok thats my 2 cents,happy motoring
 

bigjoep89

Expert Expediter
See if you can go back and do a search on a post teamcaffee made. I had the pleasure to visit with them and they have this down to a fine science.
God bless our Military and Vets.
 

theoldprof

Veteran Expediter
I cut my MPG in half!!! I traded my 15 MPG van for a 30 MPG Chev Cobalt. I think my net profit is actually more at the end of the month. But, if you factor in the garden mulch, paint, etc required for the Honeydew list, I am going broke.
:+ :+
 
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