poor mileage, is this normal?

After burning my first tank of gas I am coming up with 25.5 miles to the gallon. This is after factoring in tire size. It was mostly highway at 50mph. Does this sound right? Is 40mpg unrealistic? At what speed do you get the best mileage? Forgot to add that it's a 96 mitsubishi with 5 speed and a/c, but I have been driving with the a/c off to get more power. The a/c really robs power on the highway.

 

try running a search i came up with this but there were a bunch more...

http://www.minitrucktalk.com/showthread.php?t=50&highlight=miles+gallon

mythbusters did an episode comparing the power robbed by the a/c unit to the greater drag coefficient of driving at hiway speeds with the windows down. they got better gas mileage with the a/c running and taking advantage of the aerodynamics.

when i run my truck hard on the freeway at 75-80mph with the a/c on i get low 30's... when i keep it around 55mph i get closer to 40mpg

 

I get high 20s to low 30s when I drive 65-75 MPH. Your fuel economy does sound a bit low, especially at 50 MPH.

Colin

 

I topped off my tank (9.8 gallon tank) and added two fuel system cleaner bottles and drove 492 miles untill my car ran out of gas. All this was around town driving... and no highway use. 492 divided by 9.8 = 50.2 miles per gallon. I figure I could do better if I did less stop and go commuting. I did a engine, trans and diff oil change as well as fuel, oil and performance air filter change prior to testing out the miles per gallon. I did it with light duty aswell... everything from getting groceries to going to pick up parts from the dealerships for my bodyshop. Awesome cars.

 

I'd think that the AC tends to hurt mileage in one of these trucks more than your average car. If I had to guess I'd say the AC takes maybe 10 hp, and that's a big percentage of 45. I have a van, so maybe I have a larger compressor, and that could be why it seems to affect it so much. Turning it on seems to slow me down a pretty noticeable amount. But, when it's 90+ with Michigan humidity, it's worth it.

It seems that a huge selling point for most of the dealers is "50+ mpg!", and no one seems to get that. I get mid thirties no matter what speed I go. When people ask me what kind of mileage I get, I usually lie a bit and say 40 to 45. Honestly, if I got 10mpg, I'd still drive it....

-Andy

 

Let's not forget we are working with KM. 492 KM = 305 miles. 305 miles divided by 9.8 = 31.1 MPG. I often quote 35 - 45 miles to the gallon. This all depends on driving habits, speed and whether you are simply putting around the farm.

Jeff

 

In my truck we are actually talking about MPG... and I'm seeing 50.

 

What is that? it tops out at 25 MPH? that has to be the wierdest looking speedo I've ever seen.....

 

Mine doesn't have the extra weight of 4x4 drive trains and dumpbed hydrolic kits. I truely got 50+ mpg. Perhaps I'll try it again while carrying nothing and go for longer drives.

 

What should I be checking into to see whats wrong with my truck? I pulled the plugs and they all look perfect. I put new wire set on thats for another car just to make sure one wasn't bad. It didn't make a difference. The cap had some buildup that I flaked off and polished up. I'm pretty sure this tank is going to be worse than the last tank. In 75 miles I'm already below 1/2 tank. at this point I would be thrilled to break 30 mpg. Any suggestions at all?

 

One more thing I forgot. People are saying that they can drive 60 to 70 mph. How? I can't get past 85 kph with a tailwind going down hill with the a/c off. Did I buy a lemon or what?

 

whats the mileage of your truck? fuel system cleaners always help a little... shell gas seems to always give me slightly improved gas milage. Air cleaners in mini trucks always seem to be in bad spots for dust... behind the wheels. I sealed my box off and pipe clean air from the front right under the bumper. new air filter made a night and day difference. Don't carry uneccesary things in your truck. Tire preasures... I'm running 38 in all tires.

 

What kind of mini truck do you have??

 

I stand corrected gumball. I am certain however, that a RHD mini driving around at 25mph could probably achieve similar results. The 55 MPH speed limits mandated in the 70's was because once you go faster, mpg drops off significantly. There are so many factors effecting mpg. One of the best driving techniques to achieve better gas mileage is to shift into the highest gear as quickly as possible.

Jeff

 

96 mitsubishi, 660cc, 5 speed, 48,000 miles, 4wd. Empty load. Would having atv tires cause a significant increase in the load at highway speed? What kind of tires do the rest of you have?

 

I modded the transmission to get high gear... altho I only travel down the local expressway at the speedlimit which is 45mph. My hijet has never been on the highway but it is capable of 70mph. I've personally been paced by my friend at 60mph and it had plenty more.

 

It is my experience that ATV tires happen to be fairly lightweight. I'd say your mileage and the fact that you are 4wd probably contributes to your lower gas mileage. Give your car a good service and things should improve. I don't really have experience with mitsubishi minis... I've only seen Hijets in person.

 

My engine temp. runs straight up and down. Does this sound about right. I'm just searching for clues. Maybe my cat is restricted.

 

i beg to differ with your theory. that is not the case in all vehicles. i have had problems driving like that, it will clog up your cat and make it run like crap. it may help your MPG but you also have to keep the truck running in it's power band... you will actually waste a lot of fuel by bogging the engine. i don't get into 5th gear until about 70-80kph

i will agree that high rpm will waste fuel but you should have your truck running in the proper rpm range for each gear.

 

tune up...check carborator adjustment (mixture) ....air filter.....oil change....cat could be rob'n fuel milage....atv tires rob milage.....radials better .....driving habits affect too.....I find better milage if I avoid the highway......I run high octaine only......clean the windshield!....bugs on the glass create drag!!...last resort will be to shut off the engine on down hills and coast a little....

for me....25 ltrs will get me 340-360 km.....no highway?....closer to 400km.....the only power loss I have is when I try to pass a school bus on an uphill driving the 400 highway....right milt?

glenn

 

i wasn't laughing at you glenn, i was laughing WITH you. i can't count the times i had enough speed to pass something big and hit a hill and haD to back off, fall in behind, build a new head of steam and try to get past them on the down hill stretch screaming "GO HAMSTERS, GO!!"

 

You are right Milt. Especially these engines they do like to be reved.

 

I know buddy...but the kids on the bus were laughing.....today alone?...two card passings at the lights....five thumbs up......two pics with a camera phone...three honks with a wave(girls)...two "nice wheels!".....and about a dozen drop jaws...

sorry for the hi-jack...

glenn

 

I can't imagine taking that on the 400

 

i watched him do it, and aside from the school bus / hill combination he did just fine keeping up with traffic

 

Oh, I was thinking about trying to keep up to the traffic, it was dealing with the very aggressive pig headed hog head drivers down there.

 

It's been my experience that the biggest danger for minitrucks is rubberneckers.

My '99 Suzuki gets around 30mpg. I'm running 13" m+s street tires.

 

I kept stock tires on my Hijet, and averaged a real world 32 mpg on mine, untill TX got stupid. I kept to 55 mph.

 

In the real world, 25-35 MPG is is more the norm than the 40+ MPG dealers are claiming. Not great, but still... try to find another half ton truck that can pull 30 MPG mixed city/highway.