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Drove form Texas to Colorado on MOnday. Only getting 18 MPG on the highway at 70 and 17ish 75-80. Shouldn't I be getting better MPG? Same MPG as daily driving, back roads with some stop and go. Only 11K on truck and new fuel filter???

Thanks in advance:thumbsup
 

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Drove form Texas to Colorado on MOnday. Only getting 18 MPG on the highway at 70 and 17ish 75-80. Shouldn't I be getting better MPG? Same MPG as daily driving, back roads with some stop and go. Only 11K on truck and new fuel filter???

Thanks in advance:thumbsup
11K It's not even broken in. mine had 60K before it got over 20mpg
 

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Yep diesels have longer break in times for the motor, Most people see an mpg improvement around 20,000 miles. Also the 04.5 don't seem to get as great of mileage as the earlier motors. I see about 20mpg, little more some times, if i can keep the motor from spinning over 2k rpms and keep the EGTs under 650* and boost under 7psi.
 

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it all depends on your boost and egt's... keep that low and your mileage will go up once the motor is broken in...
 

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My rule of thumb for best economy is keep the rpms below 2k and the boost below 8psi. With the 285/70's using these numbers puts me right at 70mph non towing and getting 20+mpg. Slowing down 5mph will gain another 2-3mpg.

MikeyB
 

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Drove form Texas to Colorado on MOnday. Only getting 18 MPG on the highway at 70 and 17ish 75-80. Shouldn't I be getting better MPG? Same MPG as daily driving, back roads with some stop and go. Only 11K on truck and new fuel filter???

Thanks in advance:thumbsup
Your doing better than me. I get 16.3 consistantly.
 

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Drove 300 miles this weekend - set cruise @ 65 (with tires added in the speed was close to 70mph) averaged 18.7 and that is broken in milage, hand calculated with tire % added in.
 

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I can't break 17 m.p.g at 60 with a tail wind in my 06 and it is well broke in. I have never gotten better than 2 mpg better after break in on any of the 12 diesels ive owned.
 

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I can't break 17 m.p.g at 60 with a tail wind in my 06 and it is well broke in. I have never gotten better than 2 mpg better after break in on any of the 12 diesels ive owned.

Get a TS MP8 and you will. My dad has an 06 with just an MP8 and an Intake and he sees over 20 all the time.
 

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Keep your speed at or below 65-67 mph and it will increase your mpg. These trucks really prove that point. MANY people have learned to change thier driving habits to go along with this.

My truck is the same. 65mph and it'll get 20mpg. 70mph and it'll get 17mpg. Sucks but you just learn to slow down.
 

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my 04.5 the best I have gotten yet is about 14. Its got 120000 on it so its broke in. I don't think something is right with it. Its my first one though so I don't know, but for a stock truck it smokes a lot and its not that fast.
 

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Drove 600+ miles today...went up the hill Florida to Tenn.

At 70 mph cruise I averaged 65.7 mph @ 22.75 mpg...Also sat in two traffic jams 2 plus hours...btw over head said 24.7 when I filled up but got as high as 26.1 before Atlanta.

Using the Diesel Kleen as listed on bottle and MMO as listed

Stock truck with Amsoil air filter and 3803 tuner set on performance (did not like the way it handled, reminded me of a big block I once had that just did not feel right under 90 mph...surged to me).
 

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The best I have seen is in the 16 range.....still working on getting to 17. I miss my 01 that got 18-21 all the time with 33's......oh yeah I recently did get the overhead in the 18 range and that got me excited!!!! How bad is that!!
 

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i get 24mpg if i can keep my foot out of it
 

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but you also gotta keep in mind that on he 24 valves it vary"s w/ the programer you have on it
 

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im get'n about 16-17mpg's street.
and about 17-21 hwy.

edge set at 3 all the time.
i never let the boost get above ten unless im try'n to kill(not literally, please) some1, but other than that I try to always keep it below 4-6lbs of boost.:thumbsup
 

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Finished trip and got 28.3 on the overhead with 26.7 hand calc with average speed of 62.4 mph

Now keep in mind the speed limit was much slower today, never got above 70.5 mph as a high....No traffic jams and no AC (it was a chilly 65 this morning). Headed back to Atlanta for the week and will update run with 2 cycle mix this time...I am driving like a old man too....easy takeoffs and never removing cruise unless needed.
 

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I get between 20 and 22 on the highway pretty regularly.:thumbsup Overhead will show about 23 to 25. Speeds between 55 and 60 on Farm to market type roads. Would like to get a programer or something, but my dealership looks for that kind of stuff and I don't want to ruin my warranty. so far i've got 23.5 k on it.
 

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if you drive majority on hwy........moving up to the next tire size will also help. i t will lower you RPM's. but if you drive mixed hwy on stop 'n go's then never mind.

also a chip definately helps.
 
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