What are you guys getting?

I just recently installed a Fass and in the process I switched back to the old setup using the old style factory in-tank fuel pickup.

Now all of a sudden it seems like my fuel gauge gets to empty MUCH quicker. I get about 150 miles to a half tank. Right now I'm sitting on 1/4 a tank w/ 264 miles on the clock. I have been hand checking my mileage and it's consistantly right around 16.3 w/ the overhead reading 17.8 or so. I have never really watched my miles per tank, but it has caught my attention. If my calculations are correct, my fuel gauge is reading as if I were getting 8~10 mpg.

Could this be something to do with the Fass filters holding more fuel or perhaps the unit I put in the tank is messed up?

 

a half a tank of fuel yields me 320 miles. that is 60 percent highway and 40 percent city driving. i also have the fuel tank vent mod, so i can get 36 gallons in my tank at fill up.

 

A 32 or 33 gal fill up gets me a 600mi range give or take. I got 670 miles once but I only have about 5k so far.

 

Have you checked your oil level? That's the only place I can think the fuel can go.

Tony

 

WHOA, the most I get is 500-550

 

I just got lucky the last tank, my first 505 mile tank. I don't drive agressive, but I don't drive like a blue hair either...

 

Last fill-up a few days ago, I went 705 miles and used just over 36 gallons. Not sure why your needle would be going down quicker but your hand calculated fuel mileage stayed the same.

 

okay well seems like even when im completely empty I can only put in about 32 gallons, that's why I only get 550 miles to empty

 

What I'm starting to think is that the unit that we put back into the tank was either bent or damged. I noticed that when we did the install, I had over 1/4 of a tank before we dropped it. There was some loss of fuel, but I would guess less than 1 gallon. With the install done, I started the truck and my needle was as far left as it could go and my low fuel light was on. I felt that it wasn't right, but the tech assured me that we had lost more fuel that I thought during the install, and the Fass system took a lot of fuel to fill the filters and lines. Something told me he was wrong, but who am I to second guess a Cummins tech? Well, I know better now.

At this point, I think it's obvious he was wrong. This week I am going to let it get to empty before I fill up and see how much it takes. Then from there I guess I can go about trying to solve this problem. Nothing is quite annoying as an inaccurate fuel gauge IMO. I guess it could be worse though if it was telling me I had more fuel than I really do.

 

Just filled up today with 31.55 gallons and had gone 445 miles. This was with approximately 80% stop and go in town driving. And a few miles of highway driving thrown in.

This is about the most I ever get out of a tank because I have not been on any long highway trips that I kept my foot out of it.

I did a 150 or so trial once and got about 18-19 MPG. That would put me a little over 600 miles if I went that far and behaved myself.

 

Had my ECM Flashed 2 days ago to: TSB 18-19-04-20 .8 ZZ

Just got off a highway / 10k mtn. pass trip (2100 RPM / 70 MPH Max used cruise control )

Checked the MPG's (By Hand) = 20.16 MPG and only 23K miles on it!

Dang that should give a range of about 700 miles.

Personally I do not to run below 1/4 tank as I like to keep things cool and lubricated.

 

Avg. 730-750. Been as high as 830. But I'm patient enough to fill it up to the neck everytime also. About 34-36 gallons.

 

I here of guys getting 500+ miles out of a tank. I've never seen those kind of numbers. I usually get 400- 425 miles and fill up with 31 gallons. I drive 10 miles one way to work with 6 traffic lights (I usually catch every one), about 100 - 150 miles a week empty and the rest of the time I'm pulling a 14' cargo trailer mostly highway. I have to fill up once a week or about 400 miles. I avg 12 - 14 miles per gallon pretty consistantly.

 

right now im sitting at 300miles on half a tank and when i fill up it holds 29 gallons

 

On About 26-27 Gallons I Get Approx. 400 Miles, But I Dont Baby It Either