I have the same setup 2004.5 dually 4X4 quadcab 6spd and get 18-20 at 70-75mph according to the trip computer. I have about 11,000 miles on her now. 98% of the miles were pulling my 24' enclosed car hauler anywhere from 3500 pounds empty to 16000 pounds over weighted (try not to do that very offen). So you might want to try putting some weight on her. By the way get 14-15 pulling empty and as low as 9.5-11 over weighted. See members photo's.

 

Everyone is answering the mileage question but not the filter minder one. The dealer can replace you filter minder. They had problems with some of the ones on the 04.5's. Take it in get the new one and get the flash done. If the dealer doesn't want to do the flash just tell them that you have the white smoke on startup and want to get the flash. My mileage went up ~2 MPG with no apparent loss of power.

 

USMC2311

When I went in to pick up my truck they said the filter was actually pretty dirty so they installed a new one, so I will see if that is what the problem was or not. The increase in mileage has just really suprised me though, the reflash made a big difference. My truck actually seems more powerful and responsive now.

 

04.5 2500 4by4 4.10 gear only getting 12.8 at 70mph. what is the reflash,what does it do.

I am right there with you

 

hi guys

i have an 04.5, same in sig. with 3.73 gearing, SRW

i can pull 16.5 doing 55 mph on the highway with no load

average is 14 mpg doing the mix of highway and city driving...

JUST FOR COMPARISON IN SUMMER TIME!!

i was getting 16 MPG doing 80 with no load...

and with regular driving i was pulling 18 mpg with the regular mix of highway and city driving.
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EDIT**

Also, how do i find out if i have the FLASH for my computer system or not? is there a way to check?

thanks

 

This may sound a little nutty, but try Rain-Xing the front, side, & rear windows. I picked up 1 mpg on the highway. I doubt it would make much difference in town.

 

LMAO, you have GOT to be kidding

 

I was getting 13-13.5 before the tsb. and I average around 14.5 after the flash.
I have gotten 15 once and that was driving like a grandma!
My mileage goes way down if I do much driving above 2000 rpm.
Those numbers are hand calc.
I'm glad to see that I'm not the only one not getting 17+ mpg.

 

Casey D and others - when my truck was new last year the mileage stunk to the point I thought somethin was wrong with my truck, or that the guys reporting 20mpg were simply lying. I'm here to tell you that it really does get better with mileage and towing. Dont expect instant results, but as mileage creeps up, so will mpg. When my truck was new I had to drive like a grandma to get 15.5...now if I drive like a grandma I can get 20-21 hand calc (55-60mph). Another comparison - I used to get 12-13mpg with just my quad in the bed (big wind drag with storage box on racks). Now I get 16-18. Just hang in there!

 

lightman,

You should have rain-x the quad LOL

 

I need to buy some stock in that stuff.

 

I had to comment, your reply to his rain-x absolutely cracked me up LOL