Mpg Bad Bad And Bad

[Disel Dave]

I really don't know why but every time i get a car truck boat what ever My MPG S*cks I Love my 04. 5 325-600 QC dually and with the Quadzilla box it tows real well. But why em I only getting 10. 0 MPG? No matter where when how I drive it I drive, Even like a gandma, it gets 10 i drive it like i stole it it gets 9 I tow with it it gets 10 WHY WHY WHY ME! :{

I would love to get 14 in town and 18 highway empty but It just don't happen I have 189 miles on 3/4 of a tank that is BAD MPG. I really wouldn't know what to do if i got 600miles from a tank This stinks

PS: I did have the reflash And now My over head makes me think Im getting 11. 3 when im getting 10.

What is the pressure releve valve for the high pressure fuel rail and where is it, How do i check it something is wrong no dout!!HELP

 

[SRadke]

What are you running for an intake? Could be a MAP sensor.

 

[Disel Dave]

stock Intake with a homemade piece to replace the bafle tube.

IT was the same stock before the reflash and the same after I added the Quadzilla tow box wont do any better then 10 MPG never.

ON EDIT one thing I noted (I dont ever see smoke no mater how hard i hit it)But it sure takes off when i punch it.

 

[JApol]

Does you truck run rough? and check your oil to see if it smells like diesel, Could be from a bad injector. You could also take off the Quad for a tank and take it easy on the go pedal and see if that makes a differance.

 

[Disel Dave]

Does you truck run rough? and check your oil to see if it smells like diesel, Could be from a bad injector. You could also take off the Quad for a tank and take it easy on the go pedal and see if that makes a differance.

Nope it runs smooth as glass, and it was the same without the quad on it just less power. I read where tha quad can give 1-4 mpg better I was hoping I was a 4 but i see im not even a 1MPG better. Something is just not working right here.

 

[Motofreak]

How many miles on your truck?

 

[Bertram65]

What are you running for an intake? Could be a MAP sensor.

Is there a MAP sensor?, I thought the only sensor in the intake track was the IAT.

 

[opjohnny]

Weak liftpump ? Saw another post around here were a new one cured a case of bad mileage.

 

[swexlin]

PS: I did have the reflash And now My over head makes me think Im getting 11. 3 when im getting 10

Dave, as I had said in my previous post, that's exactly what the reflash did for mine.



My MPG has never been great with this truck. I have 4:10s, with the automatic, dually, and my "puttering around mileage is about 12 mpg on winter fuel, down from about 13 mpg in the summer.



Combinatino of cold weather, the traffic, and winter fuel, and mileage is bad. Like me, you were used to your 7. 3 with some better mileage. Ain't gonna happen with this truck, my friend.



By the way, I have had a leaky CP3 for 3 weeks now (STILL waiting on the backordered parts ), and it hasn't effected my mileage one way or the other.



Scott

 

[MWilliams]

Hello, where is the lift pump located on an 04. 5?

 

[GFrance]

Something isn't right. My 05 dually gets 10mpg to 12mpg towing my 12,000lb 5vr & 14mpg mty around town & 16 hwy. Might try getting that lift pump flow tested. Have you had it into the dealer hooked to the computer & have them shut down one cylinder at a time?

 

[Elite1]

Dave, check this thread: http://tdr1.com/forums/showthread.php?t=147612



The lift pump on the 04's is mounted on the backside of the fuel filter canister (housing). In 05' they switched to an in tank lift pump.

 

[Disel Dave]

How many miles on your truck?

My truck has 43K on it.

 

[swexlin]

Dave, your truck and mine are almost duplicates. My truck runs like a top, with plenty of power, and no smoke, except for less than 30 seconds on VERY cold mornings.



95% of the driving I do (stop-and-stop in traffic) is not conducive to good mileage. Are you daily-driving your rig?

 

[Disel Dave]

Dave, your truck and mine are almost duplicates. My truck runs like a top, with plenty of power, and no smoke, except for less than 30 seconds on VERY cold mornings.



95% of the driving I do (stop-and-stop in traffic) is not conducive to good mileage. Are you daily-driving your rig?

No I been driving my car I can't aford to feed it, I was on a few trips with the truck and it only gets 10MPG If others are getting 14-16 Why do i get 10 There is somthing that is not right I know when i was starting it cold and running 5 miles to work and doing the same at the end of the day I should not expect more then 10 but on a trip I should get the 14-16 My truck has the 3:73 rear I run 70 at 1850 RPM to 1900 I should be doing better then 10MPG.

My Power joke was the same 10 I went to the CTD cause i wanted better MPG and to try something differant. Im not sure i made the right move if 10 is all it will get. allthough the torque is nice towing. I think there is something causing the low MPG in a few of these trucks Im just looking for help finding it. I have 188 miles on all but 3/4 of a tank That is worse then 10 I have seen where many CTD 3ed gen guys are doing 18-20 highway empty with the cruise set at 70 they may not be duallys but they are the same less the 2 extra wheels I would be happy at 14-16 highway empty but im no where near that.

I need to check the fuel pressure going into the cp3 I guess, Any one send me in the right direction on how to check that.

Dave

 

[swexlin]

I should not expect more then 10 but on a trip I should get the 14-16 M

I agree. My worst tank has never been below about 11. 8. Driving 75mph with my 4:10s, I can get 14-15. Seeing as how you have 3:73s, yours should be better. By the way, I have about 19000 miles on my truck.



As I said, I have had a bad CP3 for at least three weeks now (leaking), but have not noticed too much of a difference in mileage.



Wish I could help you out more, but others more knowledgeable here will chime in .



Scott

 

[JVas]

Just something to think about.

I average 20 to 22 MPG on my truck except when I have a U-joint binding up.

Every time my mileage dropped to 17 MPG I found a bad U-joint.

 

[thealaskan]

I'd be a little peeved and looking for answers at my (dare say) dealer or a trusted Cummins tech. Or... . get fired up and take it out on the right schmucks.



I'm getting up to 13 pulling a 15K 5th wheel !! (see my 13K report)



Let us know what you find.

 

[2Gen3Gen]

No I been driving my car I can't aford to feed it, I was on a few trips with the truck and it only gets 10MPG If others are getting 14-16 Why do i get 10 There is somthing that is not right I know when i was starting it cold and running 5 miles to work and doing the same at the end of the day I should not expect more then 10 but on a trip I should get the 14-16 My truck has the 3:73 rear I run 70 at 1850 RPM to 1900 I should be doing better then 10MPG.

My Power joke was the same 10 I went to the CTD cause i wanted better MPG and to try something differant. Im not sure i made the right move if 10 is all it will get. allthough the torque is nice towing. I think there is something causing the low MPG in a few of these trucks Im just looking for help finding it. I have 188 miles on all but 3/4 of a tank That is worse then 10 I have seen where many CTD 3ed gen guys are doing 18-20 highway empty with the cruise set at 70 they may not be duallys but they are the same less the 2 extra wheels I would be happy at 14-16 highway empty but im no where near that.

I need to check the fuel pressure going into the cp3 I guess, Any one send me in the right direction on how to check that.

Dave

Sounds to me that you should look at your driving habits. If every car, truck , and boat you drive gets bad mileage, did you ever think it could be... 1. Aftermarket mods or 2. The person in the driver seat. Try having your wife drive and see what she gets. The one and only time I pulled my 26' trailer to the Oregon coast on a 2 lane hill type winding road, I still got 15 mpg in my 04. 5 CTD 48RE 4x4 3500 3:73... Sounds like it could be the driving habits in my own opinion... . Please, NO flames

 

[2Gen3Gen]

You mentioned you had a Power Stroke that got the same. Very strange! I had a 97 F350 Crew cab Duelly Powerstroke that ALWAYS GOT 14 mpg in town with 4:10's and 17 or better on the highway. It had the Automatic trans and pulling a 5ver low bed with 18k loaded on it from Edmond Oklahoma to Chico calif, with it hitting 70 - 75 on all the hills and straight of I-40, I still got an avg of 12. 7 mpg in it! I had a 100 gallon transfer flo tank in the bed but that had nothing to do with my milesge. It just added extra weight! Something here just isnt sounding right aboiut your trucks. . I for one dont have the lightest foot and have never got 10 mpg in the worst cond with any of the 4 CTD's or my 2 Ford Diesels. Once again, just my opinion for what its worth.