dieselnewbie

That's actual. Overhead read 22.9 at the time the test ended ( 603 mile mark, fuel gauge on EMPTY.

54k miles on the odo.

test was done driving 603 miles, mostly pampered, highway miles. No faster than 60 on cruise control.

3.64 too strong seems to me like a pretty big error in the overhead vs. actual.

How's that compare to any of you? Have you calculated actual before?

Are you getting more or less mpg?

Thanks for your input and have a great holiday weekend!

madhat

Oh, yeah, the overhead liar is WAY off... I've seen it 5 mpg off before...

Adaminak

That's about right for mine as well. 23.3 on the overhead is somewhere between 19.7 and 20.1 calculated.

I get the largest spread when I spend a lot of time driving downhill. There's a trip in Colorado I used to take that would put me at 33.6 on the overhead at one point of the drive, and I'd end the entire trip well over 28, but the calculated result was never better than 20.3.

12PACK

Before heading up to the White Mountains last year, I filled up, reset the mpg and was going ~ 45 in 6th gear for 10 miles or so before hitting the highway.

MPG's read over 28. Wish that was the case but I'm usually 18 town/23 highway figured by hand, keeping it ~ 60 mph.

sdmark

I see the same as the others. Reads 23ish and I am getting 19ish when hand calculated. Do you have any mods? Tire size (and tread pattern) has made a difference. For instance, with Pro Comp ATs I was getting higher mileage and the overhead was not off as much. When I switched to the Xtreme ATs mileage went down and the disparity between the overhead and the truth grew bigger. With 4.10s, you should be pretty happy with those numbers though.

Shorts

Nice mpg on that tank.

I too see a big difference between actual and overhead. Best tank to date was 20.7mpg actual showing 25.2 overhead. I usually show about 5mpg off. I've been told that my overhead may be so far off because I reset the trip odo every time. So I've been leaving the trip running to see if that closed the gap. After 3k miles it did not.

I think my tire size/comp flash has something to do with it. But that's just guessing. I want to get that reading right and see if it gets better.

etn550

All the same for me too. Best Overhead and actual is running flat interstate at night in the summer, with a lot of traffic and no wind. Overhead can get up to 27 or 28 after a few hours. Actual around 23. Normal for me is 17.5 in town and 21 hwy at 62 - 63, about 1900- 1950 rpm with my 6 speed, tires and 3.73. 4WD hurts it some due to the added height exposing more stuff under the truck.

MikeyB

My one year average is 19.7 mpg. Mostly around town with some highway mixed in. The high was 21.1 mpg, low was 19.1 mpg. No towing for the year.

MikeyB

.boB

Mine seems to be fairly accurate. It consistantly reads <0.5mpg differance than calculated. IMO, that's within an acceptable margin of error.

The overhead meter is good as a comparison. Last trip it read 19.5, this trip it reads 16. Now you know there's a problem you need to look into.

Driving at 60mph it reads 20, driving at 75mph it reads 15. You don't really care that it's off by 1-2 mpg. But you do care that the higher speed is sucking fuel like there's a hole in the tank.

OCMerrill

Mine used to be off about 3 mpg until the 35's went on. Now the speedo is off about 6 mph at 60 mph (actually running 66 at indicated 60) but the lie o meter is never more then a 1/2 mpg off now.

I am 100% stock minus the tires and a level. My best tank was 22.3 but my highway average is more or less right at 20. Run 70+ and it's in the 18's.

DodgeChallenger

.... and that is weird. My truck the O/H computer reads less MPG than it is actually doing. Checked manually many many times.

wellmax

I have a 05 2wheel drive and my over head is not too far off.
Of course i do not drive it hard and everything about is std. It had a K&N air filter in it when i got the truck, but i change it out to one of the new mopar 4" thick air filters and the mileage when down about .5 mpg, but worth it to me to insure the engine is getting clean air.

I have enjoyed the truck, even mama likes the sound of the motor.
47K miles

Rednax

Am close on to two years at 22+ mpg overall average. Nothing but some limited, light towing. (sig)

Overhead tends to read .75 high at 58 mph.