What's the gear vendor overdrive?

 

Kioti,

What 66stang tells you about the best mileage to expect is correct. I have 2008 Job 1 450 w 4:30; pulling a 12' tall 5th wheel camper with total rig at scales 25,000# including 450.

Best I get empty is 15 if going 45-50 (2k RPM's) on rural roads. Highway empty is 14.5 at 70 MPH; 12.5 at 60 MPH - go figure!! However, when it regens, which is for 10 minutes every 120 miles or so (yes that ofter) the mileage for that period is about 7 to 9 mpg running empty at 60 MPH. I use lie-ometer for the regen mileage figures, both lie-omenter and actual calculated readings are very close when running empty. Lie-ometer often say I get better than 10 towing but it just isn't so.

Pulling my 40' 15k# camper at 60 I have gotten 10 MPG once; for the most part it is 9.5; once as low at 8.5 in hills of W Virginia. Seems the same whether using tow/haul mode or not. Lie-ometer is really off when towing.

It was a bit worse when new (now 22k miles). Improvements (0.25 to 0.5 onhighway and 2 MPG in town/rural riads) were seen when I added the Job 2 air dam (helps high speed MPG) below the front bumper and got the flash last summer that eliminated the regen at idle that was causing all of the fuel in oil. If you haven't had the December 2008 reflash - get it; way better low end power and more solid and earlier shifting at lower speeds (the latter only if not in tow/haul mode).

Regarding programmers, I understand that for most, and your heavy load may be the perfect use/exception, they don't do anywhere near as much for the 450's as they do for the 250's, as they add low end HP that we have plenty of due to our rear end ratios. I understand programmer provides maybe 1 MPG improvement for the 450 (vs 3-4 with a 3.73 rear end 250) and not much power difference unless hauling a real heavyload - but that sounds like it may fit you well. And of course the best improvments and mileage (like pre-emisison-era mileage) come if you remove the DPF (and run DPF delete tunes). Thise alterations can create extra work for you if you need warranty work and feds EPA may bite you one day. Tuner forums have lots of onfo on tha If $ is no object, overdrive and the programmer/exhaust may be what you need, using OD only in selected configurations/speeds.

Mine has been in the shop so many times for so many weeks that I couldn't possibly consider a tune until I get the basics fixed. Cab off twice, wiring harness, high end turbo, 2 radiatiors, trans control module, intermittant wire harness fault, turbo cooler, leaks like I can't believe...
Love it as a tow rig, I have my "hotel" when it is on the shop, just glad I don't need to rely on it to make a living.



Gear Vendors under/overdrive transmissions the most awarded auxiliary transmissions.

Gear Vendors Under/Overdrive, Ford 4X4 Wheel Drive auxiliary transmissions.

is a $3k solution that will give you the equivalent rear end ratio of a 250 (3.73) or even lower if you ask them. A 450 has more drag thana 250 but the lower RPM's and turbo boost should get an extra MPG or so for any given speed.

Best of luck to you.

JohnD333

 

The gear vender is A good option, I don't tow Alot of weight so I installed 3:73 gears.

 

What kind of mileage are you getting unloaded?

 

Unloaded I drive faster, between 70 to 75 MPH and get 14MPG.

 

.... Our 450 with 4.30s gets 8 to 9 towing 19K over the flatlands of Eastern Washington. You're smoking crack trying to get people here to believe you got 16-18 towing almost 30K. Could you actually tell that to somebody in person and hold a straight face?

 

Yes I would tell you to your face and one better My old Chevy showed up at my place last night with it's new owner turns out a local bought it so one better mouth O mighty why don't you come by here and I will show you in person!
Dude I have nothing to lie about period.
I had an edge jucie box in it and on the 2nd setting the truck will get that milage all day long loaded. Let not be idiots here it would not get that up hills.

 

We have 3 Chevy durajunks in my family. 2002, 2004, 2007. My brother and father like theirs ok but none of them do better than 19-20 unloaded with programmers. Fully loaded they are in the 10-12mpg range. So go back to school and get a calculator.

 

Like I said the Chevy is around my neck of the woods again so unless your coming out to see for youself I have nothing more to say to you about the Chevy.
The topic was about my for not my Chevy.

 

Here is my experience, all weights GVW assuming my 250 weighs in at 8000 (people, toolbox loaded and lots of stuff)

16ft tag along cargo trailer, GVW 13,000 = 11-12 mpg average
20ft tag along cargo trailer, GVW 16,000 = 10-11 mpg average
36ft fifth wheel cargo trailer, GVW 23,000 = 9-10 mpg average

figures using the truck "lie-o-meter" that people call it
interstate, city, and 55 mph state highways included
I always drive the posted speed limits and don't drag race
I always use ULSD, could be an issue for some folks who forget to pay attention to that
Tire pressures at the max

My experience with an '05 Duramax 3500 dually with Superchips programmer at level 2 for towing? Virtually the same. It had a lower rear end gear so starting from a stop was easier, mpg's all within 2 mpg. No way ever saw high teens with ANY trailer.

Take it for what it's worth. I'm giving you numbers based on 800-1000 mile weekly runs.

 

You probably didnt think about it but the chevy has smaller tires which also help the ratio. Keep in mind that in the past chevy basically uses one very small tire size. So if they said 3.73 then thats what was felt on the aspault. However, if Ford says 3.73 then thats with thier smallest tire size. Since Ford has several options for tires and wheels most people end up with larger diameter tires thus leading to less than 3.73 on the final drive ratio.

 

KIOTI, are you telling us everything about your '04 chev? I KNOW this thread is not about your Chev. but your MPG's are impossible to compare with the 6.4 performance.

You mentioned a tuner. Did you run a Banks system or something like that too? How much did you mod the Duramax you had? Did you mod the Allison? The guys here don't like it when I say that the Allison was a better feeling trans. than the Torqshift I have now.

I would say that you are justified in being frustrated with your MPG situation but there is NO way you can expect the '09 Isuzu, International, or Cummins diesels to give you upper teens with that much weight behind them. Sorry for the bad news.

 

Sawtooth, you're right. The 3500 I had was a 16" tire, my 250 is an 18".

No slack 'round here!

 

guys dont bite my head off when i say this...Maybe (and I say maybe) this chevy was actually a good one (i know that sounds far-fetched) and maybe he was super easy on it and babied it...btw Kioti can you tell me again which truck you had? Was it a dually? What was the gearing? and what besides the programmer had you done to it? I'm kinda trying to play devils advocate on this....Rick seems like a really nice guy Maybe he babied this truck and the 450 really isn't broke in and maybe it has some underlying problems that need to be cured

 

Well, I couldn't even get the Duramax guys to believe 16-18 mpg's pulling a load was possible. I mentioned this on a D-Max site and everyone there called BS also. Every Tuner, Programmer, or Mod out there was mentioned but, no one could claim mileage even close to that. Even pulling half the weight 12 seemed to be the highest.