2005 Power Wagon MPG

I've tried to explain a few times about how the DTE hangs out for about 30 or so miles before starting to come down. I decided to take pics right after a fillup to show gas mileage and the 30 - 40 mile discrepancy on the DTE.

I've discovered through trial and error that 68 MPH seems to be the sweet spot for my truck on the freeway. The trip between Albuquerque and Santa Fe on I-25 is not a nice flat trip. There is an overall elevation change of 1,700 feet and it's fairly hilly (up and down) the whole way.

I took eight series of pics starting at the gas station just over halfway between SF and ABQ on my trip home. In each series, I got The Distance To Empty (DTE) Overhead Console Odometer (EODO), Overhead Console MPG (EMPG), Speed and Dash Cluster Odometer (ODO). Note, the actual pictures are further down.

  • 1st
    • DTE: 436
    • EODO: 13.5
    • EMPG: 15.3
    • Speed / ODO: 68 / ???
  • 2nd
    • DTE: 436
    • EODO: 24.1
    • EMPG: 16.4
    • Speed / ODO: 68.5 / 24,931
  • 3rd
    • DTE: 439
    • EODO: 27.5
    • EMPG: 16.8
    • Speed / ODO: 2 / 24,934
  • 4th
    • DTE: 436
    • EODO: 28
    • EMPG: 16.4
    • Speed / ODO: 0 / 24,935
  • 5th
    • DTE: 439
    • EODO: 30.7
    • EMPG: 16.7
    • Speed / ODO: 60 / 24,938
  • 6th
    • DTE: 439
    • EODO: 32.3
    • EMPG: 16.8
    • Speed / ODO: 0 / 24,939
  • 7th
    • DTE: 434
    • EODO: 35.2
    • EMPG: 16.4
    • Speed / ODO: 0 / 29,492
  • 8th
    • DTE: 434
    • EODO: 36.7
    • EMPG: 16.2
    • Speed / ODO: 0 / 24,943
  • 9th - The next morning
    • DTE: 415
    • EODO: 52.3
    • EMPG: 15.9
    • Speed / ODO: 0 / 24,959

You can see in series 1 - 2 that EMPG is rising and I've gone 24.1 miles without the DTE changing. In series 3, you can see the computer tried to compensate for the MPG now at 16.8 by increasing the DTE 3 miles. By this point I'd gone 27.5 miles and my DTE is increasing. I've seen it go up a little over 30 miles in some cases.

In series 4 I had already reached Albuquerque and sat at two traffic lights for a little bit. The EMPG went down a bit and the DTE computer compensated again by dropping 3 miles. I really don't think the computer has a clue, but it's attempting to compensate by refactoring and averaging previous tank data.

By series five I had been travelling at 60 MPH for a little while on Paseo Del Norte which is a major six lane thoroughfare between the East and West sides of Albuquerque. My EMPG went up and the trip computer again attempted to compensate by going up 3 miles.

In the 6th - 8th series I had sat at a few stoplights and finally arrived at home. The 7th series was about one mile away from my house doing 40MPH, and the 8th was when I pulled into the driveway.

The 9th series is the next morning. The console read 434 and steadily dropped on my drive in to work where it ended at 415. The drive was through standard city traffic and decently heavy traffic on the freeway (doing about 40MPH).

Overall, I had travelled 35.2 miles before I dropped below my starting DTE of 436 miles. By the way, the AC was on whole trip set to level 1 on the blower with coldest setting.

In conclusion, if we take the 439 on the DTE and add the "missing" miles before it dropped to 434, then we have 471.3 miles. If we take the average 436 and do the same, we get 468.3 miles. If we take the morning after and add the DTE with the EODO, we get 467.3 miles. On a full 34 gallon tank at the final 15.9 EMPG, we'd expect 540MPG for similar driving conditions.

Do I think I'll get that? Heck no. The best I've been able to get is 461 on the DTE and 33 miles before it started dropping. 461 + 33 is 494 and my usual average is 14.5MPG (manual calculations, not overhead console based). I usually do something to screw it up like a quick off-road trip in 4-hi or 4-lo, or I end up sitting idling for 15 to 20 minutes (like waiting on the wife). I'm going to try my hardest this tank to not do either of those to see what the results are.

Click on a picture for a larger, higher resolution view.






































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