Running HWY only 15.2 in town only 13.2 Do these numbers sound low?

15 MPG on the highway? Man I was pissed at the 24 MPG total I was getting Tuesday driving to pick up my new Ruger GP-100 SS 357 Mag. Was bucking a strong head wind. On the turnpike I was hitting 28 but on the State Routes it dragged it down to 24. But mine is a 2004 4X2 with 3:73 gears and an auto. When was the last time you changed the air filter? Don

I realize yours is 2wd, but is that hand calculated or off the overhead?

Overhead and my overhead is off by less then 0.5 MPG checking it by hand. The thing most people don't understand about the overhead mileage is you must reset it every refill to get an accurate reading. Also if you reset between fill ups you will not get an accurate reading. The other thing is where I live (the Ohio valley) we are as flat as the desert valley, so this also aides in better fuel mileage along with tucking in behind a big truck on the highway.Don

Overhead and my overhead is off by less then 0.5 MPG checking it by hand.

The thing most people don't understand about the overhead mileage is you must reset it every refill to get an accurate reading. Also if you reset between fill ups you will not get an accurate reading.

The other thing is where I live (the Ohio valley) we are as flat as the desert valley, so this also aides in better fuel mileage along with tucking in behind a big truck on the highway.

Don

Did you just check it once?

When my truck had 10K miles on it the OH was within 5%, then as mileage grew so did the error. My error normally ranges from 8% to 25% off, and it's not the smarty that does it because I get the same results on stock tunes. I have yet to see anyone's overhead that is consistent or accurate. Most check it when fairly new and never check it again, but Dodge makes the mileage increase with miles because the motor "should" break in. I'm not saying your wrong, just stating that if it's accurate you have a very very rare truck. Generally when people check it again with some miles on the truck they learn how inaccurate it is.

I reset every fillup and track it. In 2007 my avg error was 3.64%, 2008 it was 10.95%, 2009 was 17.46%, 2010 was 17.5%, 2011 was 18.0%, and so far 2012 is 14.1%. As you can see the average has peaked at about 17-18% (less than 1K miles driven in 2012 and my last error was 8% so that really dropped the average of the 4 fillups). I just do the simple math of 20% error and it's generally pretty close, but like I said 8-25% swings do occur.

Here is a sampling of the variance of the error.

Well nope I have not tracked it, to be honest I checked it about a dozen times with in the first 10K miles and have never double checked it again. So now I'm going to have to check it out again. I have done hand calcs every now and then just never double checked the OH.Don

my 05 gets around the same milage. i just figured it was because of my mods.

Well I finially got out on the interstate and running 60-65 she is getting 17. So I guess it's not to bad for plain stock, but it really sucks the fuel in town 12-13

Looking at your sig line your grossing 11K and a dually to boot. You should be tickled that your getting as good as you are. try paring back some of the weight your carring around and the milage will go up.

Rule off thumb in drag racing is you need 1hp for every 10lbs of weight more than the other guy. It kind of factors in wind resistance and things of that nature which grow exponentally the faster you go. But you get the picture. Your putting a lot of downward movement on the throttle, just to move the extra 4000lbs to the speed limit.

--- Update to the previous post...

Looking at your sig line your grossing 11K and a dually to boot. You should be tickled that your getting as good as you are. try paring back some of the weight your carring around and the milage will go up.

Rule off thumb in drag racing is you need 1hp for every 10lbs of weight more than the other guy. It kind of factors in wind resistance and things of that nature which grow exponentally the faster you go. But you get the picture. Your putting a lot of downward movement on the throttle, just to move the extra 4000lbs to the speed limit.

I believe JL is talking about the 05 and not the 01.

Thanks for catching that.

OK I have burned thru three tanks a fuel all hand calculated and using the overhead. All three are combined city highway. H = hand calculated O = overheadTank one: H = 17.9 O = 19.1Tank two: H = 18.7 O = 19.7Tank three : H = 19.9 O = 19.7So I looks like not only is my overhead no longer accurate it is not off by the same amount! :cookoo:Don

My mostly in town is 14.6, Hwy is 16.5 and that's with some red light driving. Never been able to get long distance on hwy only. Might take a trip to Vagas, that would be some flat fuel mileage.

My mostly in town is 14.6, Hwy is 16.5 and that's with some red light driving. Never been able to get long distance on hwy only. Might take a trip to Vagas, that would be some flat fuel mileage.

My 05 does about 16 overall daily driving but 2 years ago my wife and I took a vacation and went to phoenix and over to the colorado river up to the north rim of the grand canyon and over to lake powell and through the rockies up through denver and back to ND for about 4500 miles in 10 days and the 05 did an overall trip average of 19.8 mpg driving the speed limits everywhere and running Schaeffers soy shield plus in the fuel. Had the smarty JR on level 2 the whole trip, I think we could have broke 20 overall had the JR been on level 3 as it seems to do better mileage on 3.

I just turned 488.3 miles in three consecutive trips to and from work (75miles one way) took 25.35 gals to fill up for hand calculated 19.26 mpg over head said 24.3mpgs. I live and work in what is considered the foothills of the Smokies. Travel the I-85 corridor between Spartanburg SC and Charlotte, NC daily. It's rolling hills to and from with max. 5 mins idle time going and around 10 mins. on the return trip. 70-80 mph depending on traffic with some momentary stop and go to be expected either direction. Using Murphy's (wal-mart) B5-B20. Not to shabby for a stock I think '06.

I have yet to break 300mi on 25 gallons..

I have yet to break 300mi on 25 gallons..

At 14 mpg you get 350 miles out of 25 gallons. Your fuelly says 14.1 mpg. Help me with the math.

the last two fuel-ups were $50 fills, so they were partials. I'll go fix it now.but you're right, I HAVE broken 300mi from a tank.Here's my last few full fill-ups:307 (20.3 gal) 15.1 mpg224 (23.2 gal) 9.7 mpg302 (24.1 gal) 12.5mpg

Just did another 402 mile trip to FL. and got hand calculated 19.43 mpg running 72-78 with some spurts to 85 to get around traffic. Again using Murhpy's (wal-mart) B5-B20. The return trip was pulling a 10k load and a wood burning stove in the bed. 65-70 with spurts to 75. Will be filling up Thursday or Friday, overhead is showing 19.8 so probably 13-14. I'll update when I fill up.

I average ~20 on highway 65-70 mph.

I average ~20 on highway 65-70 mph.

Overhead or hand calc?

Calculated overhead usually reads 22. towing my 30' weekend warrior about 14 when its flat