Fuel Mileage enhancement

[KQueen]

Have 03 Dodge Cummins 4x4 crew cab long bed 5. 9? Any ideas on best way to enhance timing and other reasonable solutions? Any suppliers for these products would be very helpful. Thanks!

 

[Joseph Donnelly]

There are several articles in TDR Issue 61.

 

[rscurtis]

I have the same vehicle with the standard cab. On my return trips (moving) from Chambersburg Pa. to Huntington , LI, with an empty truck, my overhead will consistently show 24. 3 mpg by the time I get to the GW bridge. Truck is stock except for the Rokktech timing sensor and the Dynatrac hubs. I drive with the cruise set at 64 mph. I generally fill up in Chambersburg, return to Huntington, drive locally for 9 days, and can return on the same tank of fuel, for a total distance of about 650 to 700 miles. I have installed the tank vent mod, so I'm starting with a full tank. Before these mods, 20. 0 was about the best it would do. Also running Amsoil series 3000 5w30 oil.

 

[JDiepstra]

I have the same vehicle with the standard cab. On my return trips (moving) from Chambersburg Pa. to Huntington , LI, with an empty truck, my overhead will consistently show 24. 3 mpg by the time I get to the GW bridge. Truck is stock except for the Rokktech timing sensor and the Dynatrac hubs. I drive with the cruise set at 64 mph. I generally fill up in Chambersburg, return to Huntington, drive locally for 9 days, and can return on the same tank of fuel, for a total distance of about 650 to 700 miles. I have installed the tank vent mod, so I'm starting with a full tank. Before these mods, 20. 0 was about the best it would do. Also running Amsoil series 3000 5w30 oil.

Not to flame but I hope you do not think the overhead is accutate. If you have the tank vent mod, you probably use what, about 38 gallons? Take 700 miles, divide it by 38, and that's 18. 42 MPG. Use your 650 and divide by 38, that's 17. 1 mpg. 38 gallons times 24. 3 mpg would be 912 miles per tank.

 

[rscurtis]

You forced me to do my mileage calculations since May of this year, but I don't think you're going to like the results. The average calculated mileage for my last ten tankfulls is 20. 8 MPG. Averaging the overhead for this period shows 20. 9MPG. The 24. 3 figure starts to go down as I wait at the GW bridge, the Cross Bronx, etc. It is further dininished by a week or so of local driving. I generally add about 10 gallons of fuel during that time, which leaves me plenty of fuel for the return trip with 500 to 1000# of weight in the truck. When I refill in Chambersburg, the OHD is typically showing 20 to 21 MPG. The average speed for this loop (10 trips) is 36. 8 MPH. On a return trip from Coolspring to Huntington, The actual MPG was 22. 3, the OHD 22. 4, and the average speed was 51. 9 MPH. We're not done yet-it gets better. My best return trip with no traffic and probably a tailwind was 26. 5 calculated, 25. 1 OHD, with an average speed of 53. 5MPH. The fuel guage showed 7/8 full after 273 miles, but I consider this trip an anomaly and not necessarily repeatable. For a DTE figure for straight highway driving, I think 22MPG is a reasonable #.

 

[NBeebe]

My average for the last 8 tankfulls is 21. 16 MPG (hand calced). I generally get 650 to 680 miles on the tank before the low fuel light comes on.

 

[Matt400]

I am not so sure changing timing on an 03 is such a great idea. I bumped my 05 by 3 degrees but when I tried that on my 03 I got engine knock pretty noticable.



I think the 03's were not retarded as much due to lighter emission regs than my 05. I forget the exact numbers but the engine sticker on an 03 has higher Nox than the 05's do.

 

[Gus's 03]

on the tone ring from the factory theres 3-4 degrees of slop... depending how it was installed at the factory it could be good or bad. my tone ring is advanced almost 7 degrees from the center of the stock position... i have no rattle issues, and exelent economy, average tank is 700-750 miles...

 

[Matt400]

my tone ring is advanced almost 7 degrees

wow! and you don't get any CEL from the cam/crank sync being out? I never heard of anyone going that far. I calculated each tooth is 6 degrees.

 

[JDiepstra]

You forced me to do my mileage calculations since May of this year, but I don't think you're going to like the results. The average calculated mileage for my last ten tankfulls is 20. 8 MPG. Averaging the overhead for this period shows 20. 9MPG. The 24. 3 figure starts to go down as I wait at the GW bridge, the Cross Bronx, etc. It is further dininished by a week or so of local driving. I generally add about 10 gallons of fuel during that time, which leaves me plenty of fuel for the return trip with 500 to 1000# of weight in the truck. When I refill in Chambersburg, the OHD is typically showing 20 to 21 MPG. The average speed for this loop (10 trips) is 36. 8 MPH. On a return trip from Coolspring to Huntington, The actual MPG was 22. 3, the OHD 22. 4, and the average speed was 51. 9 MPH. We're not done yet-it gets better. My best return trip with no traffic and probably a tailwind was 26. 5 calculated, 25. 1 OHD, with an average speed of 53. 5MPH. The fuel guage showed 7/8 full after 273 miles, but I consider this trip an anomaly and not necessarily repeatable. For a DTE figure for straight highway driving, I think 22MPG is a reasonable #.

Godo post! I think I was just mad at my overhead!

 

[p-Bar]

never heard of an overhead being that accurate

 

[JHMiller]

A solid 20 mpg

My 03 crew long box 4x4 gets a solid 20-20. 5 on the cruise @ 78mph. I've added a 4" Pinnacle Power Exhaust system(big increase in performance), a cold air intake from PSM, a Roktech crank position sensor(down to 1/2-1 degree advance, too much rattle in town @ full advance), an Edge Juice/Att on 4(race position, best mpg, I just drive like normal), and an Access bed cover from Agricover. I suspect the bed cover plays a big part in keeping the mpg up at higher speeds in the Wy wind.

Today I'm adding a Nano air filter from Amsoil and suspect it will add something. I've had one before but not enough miles to really document solid changes but I do believe it gave me 1/2 plus mpg.

Before Dodge reprogrammed the ECM with the safety recall, cruise control issue program, I documented 21. 4 mpg tank after tank so I believe the Smarty programmer could also add mileage as apposed to the ECM fooler Edge.

I sure wish someone would pop for a Ram Implosion Wing as those customers are talking real mileage. Come on you Hot Rodders with extra cash, just think how cool your Ram would look with a huge Rams Horn on the tail.

O yeah, I've a 4" Rokktech Silent Might muffler(used) and a 4" down tube(new) I need to sell. Give me a holler if your interested..... john