And.... Trip back from the dealer then all around town driving for the past two weeks and... 18.5MPG hand calc..! Not bad for the 6 wheeler...! No mods - not even a bed cover and intake - yet!

 

With the G-56 and stock wheels on the highway you must really be taking it easy. I think stock on my truck I was at 2000 RPM at 65 MPH. Sweet spot was around 63 MPH where I saw my best mileage, which was about 18.1 MPG all highway driving. Lift and mixed driving i am happy at about 15 MPG... Pretty good mileage for the amount of metal your swinging around!

 

When I got rid of the 2500 for the Tacoma I thought that I was going to be getting 20+ MPG! NOT HAPPENING- - - - -16.5 to 17.2 is the best that I can get and that is with NO LOAD. The only reason that I havent got back into another 2500 is the Fuel costs and I dont need the size and capability anymore. I sure do miss it though......

 

Wow are those two truck at the opposite ends of the spectrum! My Dad's Taco isn't doing so hot for fuel mileage either, but he's happy to just putt around in it.. Just can't convince him to step up to the bigger truck...

 

My 07 5.9 was built on Dec 30th 2006. one of the last days they put in the 5.9. I got the new and IMPROVED G-56 witht he higher gearing. Going 70 I am at 2000 Rpm so makes it nice. I cruise at 65 and am right at 1900

 

I have been taking it easy - it's funny, this thing as so much torque there is no need to drive it any other way. I think at 70 I'm at 2000 Rpm also but most of the driving on this tank has been around town. I'm impressed. It's doing better than my Duramax, but then again I had a programmer on that and couldn't keep my foot out of it

 

I know a guy who just got a Tundra. He's lucky to get 15, downhill off a cliff. He gets about 7 towing a camper. He might be paying less per gallon than me but he's spending more by the time the week is up. I'm getting right at 22 now. Leaving 10 minutes earlier and taking my time is worth about 3 to 4 mpg.

 

I just got back from a NC to PA trip and got 17.5 hand calc w/gps solo and 14.6 with a 3500# trailer coming back. Speed was kept at 70 (1800 rpm), so I was happy with that. I'm installing a fuel catalyst this weekend so hopefully I'll see an increase there.

 

If you have a 2006 G-56 you will not get 70 at 2000 RPM unless you have taller than stock tires. Normally it is going to be 2100-2200 RPM. The 07 changed the gearing which allows for reduced RPMs on the highway. However, if you are getting that mileage with stock tires at those higher RPMs, if you drop your RPMs down to 1800-1900 you will even see better fuel economy. Seems the above 2K RPM is the point which these trucks start drinking the diesel....

 

Your right - I just made a run to get some pipe work - It's around 67 at 2k.. That's fine by me

 

Wouldn't complain about that fuel mileage running that fast, wonder what you could get if you slowed down. Probably able to get 20 MPG!!

 

I hand calculated about 6 tankfulls in a row when I first got my 2500 with the G56. All were right around 18.5. Never any load or towing. I didn't see any difference after being reflashed. I'm not complaining about mileage (plenty of complaints about CEL's, but mileage is pretty good). The display always shows around 20 but we know it's optimistic.

 

I guess there is something to be said for having kept my older truck. The last two tanks that I hand calculated were 21.10 and 21.97mpg (under 70mph). Around town I'm able to get in the 18's.

Unless fuel prices drop drastically, I think I'll keep my '03.

 

HA.I did the same thing.Even driving like my grandpaw I dont get anywhere near what was posted on the window sticker.2007 V6 auto 4x4 crewcab.Im 6'4 and it is a little cramped,compared to my last truck my wife says its a girls truck,boy that was hard to swallow.LOL,im going back as soon as I can !!

 

RPMS are everything. I have owned all brands of diesels at one point or another and noe really ever got the milage I had hoped for this truck included. Anyways this weekend I was taking my ATV to a riding spot about 90 miles away. I stopped a fueled on the way out. This trip normally takes around a half of a tank round trip. Well I decided to try easing around and keeping the truck at 60 to 65MPH instead of the normal 80 to 90MPH.
I made it there and back on less than an 1/8th of a tank. Thats pushing 35" tires. I just wish I had set the trip meter and been able to hand calculate the milage. In any cas it made a believer out of me so if you see a silver Dodge getting passed by everything on the road in Texas, it's most likely me.