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Yep, I have a running list of truck wants too, fun and scary. How long will it take to recoup $4400 of performance and mileage parts on my list? At $4.30 a gallon, and going from 14 mpg overall to 17 mpg, it will take 81,178 miles. If I can get to 18mpg, it drops to "only" 64,465 miles. Either way, a pretty darn long payback, so someplace in there is the fun factor of an extra couple hundred pounds of torque. But then, add in the cost or rear tires quicker and the payback gets a bit longer. In the words of my high school buddy after losing a transmission in his 440 6 pack GTX at an unspecified speed on I-74 one night, "If you wanna play, you gotta pay." Somethings unfortunately never change.
 
If I found this forum before I bought my truck, I would have more than likely got a 5.9 Cummins instead.
Amen to that ... I am looking a taking the hit and trading in 6.7 in on a 5.9 ... fuel economy will pay for the negative equity the ding me for on the 6.7

Not impressed at all
 
Amen to that ... I am looking a taking the hit and trading in 6.7 in on a 5.9 ... fuel economy will pay for the negative equity the ding me for on the 6.7

Not impressed at all
Thats why im going to dump :$: into my truck to get the milage back. Also get the longevity and reliability back.:thumbsup
 
The primary point of running the Dynatrac kit is to get rid of the unit bearings which when the time line is stretched out far enough will fail; unless it happens in your driveway they generally fail suddenly and leave you stranded probably with a few other broken parts.

In my opinion if there is any mileage gain to be had with the kit then it would be best to install it early on.

Of course the folks who trade trucks every few years and never get into the high miles don't have much to worry about with the unit bearings.

Other companies make manual hub conversion kits at a lower price than Dynatrac.



If you purchased your truck in the early days of the 07.5 then the issues weren't documented on the internet and there wasn't much to research, I do know from experience that by Sept of 2007 there was plenty of info regarding the poor fuel mileage and CEL / turbo issues.

It blows my mind when I see fuel mileage complaint posts started by people who just purchased trucks and :CRY: about how nobody told them that the mileage on the emissions trucks isn't in the same league as the older trucks. I don't understand how someone can sign away 40k on a truck and not even bother to do basic internet research on what they're buying.
I did do the research and at that time I heard nothing bad about Cummins 5.9 or 6.7. Also since I traded out of an 02 gas Dodge and had no trouble out of that truck I thought I would not have any problems.

I dont expect this truck to do 25 miles to a gallon but, I did not expect to get less that 20 on the highway either and thats what I do mostly. When your gas truck gets 17 on highway and diesel does the same their is a problem.

I wanted a diesel for their milage and thier ablity to haul very heavy loads.

Also I am stating facts not crying about it.

I will fix my truck and go on with life.:thumbsup
 
It seems as though we all realize that our pickups aren't gonna be fuel sippers. We would have all bought cars if that wasn't the case... but when you go from 20 mpg in a 5.9L to 15 mpg in a 6.7L (with basically the same pickup otherwise), the transition should be a little shocking. Have a heart for the poor guys just tryin to recoup some of those lost bragging rights.
 
Last summer I traded in my 92 F250 supercab 4x4 460fi 4sp auto for the Ram. If I drove 55, I'd get allmost 11mpg. I mostly drove 75-80 and got allmost 8 mpg. Towing a 25' trailer, 6mpg or less, depending on terrain and headwind. At 75-80, the Ram get over 17 mpg, and it doesn't care if I'm at 1200' or 8000', same power. My ford had to be floored and really drank the fuel at higher elevations. So for the locomotive like power, and way better MPGs, I don't think you can beat these DCs, Especially if you tow anything, or carry any weight at all. My 2 cents.
 
I traded in an '03 Hemi 2500 QC to get my 6.7L. On at trip the Hemi might get 17mpg at 60-65mph, if I was careful. Around town it got about 11-12mpg. My last tank on the 6.7L was 18.5mpg doing the same "around town" driving I did with the Hemi. And yes, that is hand calculated, not from the overhead. Where else can you get an 409 ci engine moving around 7500lbs of truck AND get that kind of mileage?? No complaints here!
 
seems some just get better mileage then others straight from the factory which is odd.
 
seems some just get better mileage then others straight from the factory which is odd.
Is it some trucks or some drivers that are different?

In my wife's minivan I can consistently get 5-7mpg better than she can (based on the overhead which has seemed accurate). I generally drive faster than she does but I'm gentle with the throttle when it doesn't need it. I believe she "pulses" the throttle to accomplish this. But her mileage is no lower than the EPA specs and most of her friends are getting with the same minivan. But mine are better.

I can return from a freeway trip with the mpg over 30 and she never gets better than 22. Around town she is 13-16 and I am 16-20.

She doesn't drive the truck so I don't know if it would have the same effect there (and harder to notice too without instantaneous mpg readings).
 
Is it some trucks or some drivers that are different?

In my wife's minivan I can consistently get 5-7mpg better than she can (based on the overhead which has seemed accurate). I generally drive faster than she does but I'm gentle with the throttle when it doesn't need it. I believe she "pulses" the throttle to accomplish this. But her mileage is no lower than the EPA specs and most of her friends are getting with the same minivan. But mine are better.

I can return from a freeway trip with the mpg over 30 and she never gets better than 22. Around town she is 13-16 and I am 16-20.

She doesn't drive the truck so I don't know if it would have the same effect there (and harder to notice too without instantaneous mpg readings).

I think it's a combination of the two. There are so many variables with the 6.7's such as flash versions etc. That coupled with different driving habits can make for drastically different mileage from one truck to the next.
 
I Have Been Reading With Interest. I Get 18.5 Mpg Empty And 10.5 Mpg Pulling My Toy Hauler Loaded With Gear, 100 Gallons Of Water And A Full Dressed Harley. With 4x4 Truck And A Topper I Think That Is The Best I Can Expect. I Read All The Articles About 25 Mpg, But Can't Figure Out How They Do It. My Total Cost Was 5" Exhaust From Turbo Back 275.00, Quadzilla Xzt Chip 265.00, And K&n Filter To Fit Inside Original Filter Box 75.00. So For 625.00 I Went From A Dog Pulling A Trailer With Milage Of 8.5 Mpg And Empty 14.5 Mpg To A Very Responsive Pulling A Trailer At 10.5 Mpg And A Good Running Power House Empty At 18.5 Mpg, If I Am Looking At Anything Else It May Be An Air Deflector For The Trailer, Or Manual Hub Locks For The 4x4.
 
i use cruise control as much as possible. "pulsing" the throttle will kill mileage on any vehicle. the key to good mileage is a slow and STEADY throttle. keeping out of boost helps too.
 
Some have reported opposite experiences with fuel mileage and the cruise control, I haven't measured it myself but I have noticed when the CC is on and I approach a hill the rail pressure shoots up much higher than when driving with my foot.
 
Some have reported opposite experiences with fuel mileage and the cruise control, I haven't measured it myself but I have noticed when the CC is on and I approach a hill the rail pressure shoots up much higher than when driving with my foot.
true enough. some people inadvertently pulse the pedal causing poor mileage, that is where cruise will help. kinda depends on the terrain i guess. all flat around me so I just set it and let it ride.
 
I have been using the cruise more just to see and the overhead is almost 2 mpg higher (especially on the highway), and hand calcs are around 1.5 higher. I just ran 400 miles at 63-78 mph, almost all on cruise, except for about 20 small towns to slow through, and another 40-50 miles of suburban driving. OH is showing 18.6 mpg, which means about 17-17.5 actual. I am noticing that the truck is getting better mileage all the time--just passed 3700 miles. First oil change was just before the trip, and that also seems to coincide with better mileage. I made the same exact run last weekend and got almost 1 mpg better on the OH this time, same cruise control activity.
 
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