My 06 has only 1600 miles and i have not been able to get 13mpg yet. Currently it reads 9.7mpg . I had a ford 6.0 and only got below 10 when pulling about 16-18k at 70+ mph. Recently the weather has been colder here and it seems to cut in and out at highway speeds and doesn't seem to have the power that it should. Is their anyway to check for problem codes, or does it have to be taken to the dealer. Sure seems like their is something wrong. Usually i have been getting in the 12's for mpg . As soon as i hook up to my snowmobile trailer 8*20' with two snowmobiles in it (maybe 1k) it instantly goes down to ten or below (as bad as 9mpg). Anyone have any ideas, i realize the motor is not broke in, but i drove an 05 earlier this summer that was getting 15 in town and 17+ on the highway with no miles on it .

 

Same issues here! Can't get over 11.9 hand calc'd on the highway. Going in tomorrow to get reverse lights fixed (I hope). Also have a highway intermittent vibe/shake and shudder when I stop. Only 4600 on the clock, needless to say I am worried. Traded my perfectly fine 03 for what I thought was my dream vehicle?? Later.

 

definately something wrong with your truck....I have an 06 4x4 2500 with auto tranny and hand calc with mixed city/suburban driving I get between 14.6-15.9. highway driving I avg 18.6 ...sometimes if flat, no wind, etc....I can get in 19 range. If wind or I am pushing over 2000 rpms it drops to 17s....

i would make them run diagnostics.....

 

U got problems

Start by examining how you drive...then investigate issues with the truck....

My '06 gets great mileage....21-22 highway...15ish city...12 when its really cold and I warm it up alot...I've driven over 700 miles in 2 days...country, city, and highway...35 gallons in fuel +/- a gallon or so.....

 

I am about in the 15.5 to 16 mpg range with 1200 miles on the truck. I'm glad you mentioned the cutting out feel you are experiencing. I too have noticed what I thought was this feel but had written it off as maybe bumps in the highway, but now I am convinced that I am feeling what you too notice as cutting out while driving highway speeds.

Other than these two concerns, I like this one much better than the '03 I launched.

 

man ther is somthin deffinetly rong with ur truck, you might otta check the mpg manuely. i dont see how your gettin that bad, thats still a few better than my 98 chevy 1500 350ci gasser gets

my truck (03 4x4) gets about what yalls is gettin, 16 avg with a banks chip, ram air, and intake. i dont know what the hell is goin on but my moms f-250 4x4 reads 22 mpg but is gettin avg of 20 and she has some s*** no brand 50 hp chip, i dont see how she gets that good of milige. I man she is a girl and is easyer on the gas than me but should it really get make that big a difference?

i would still take my 2500 over her 250 any day even if i was gettin as bad a milige as you. im in love with it

 

My '06 gets great mileage....21-22 highway

My 03 gets 99 MPG immediately after resetting the overhead going down hill in Mexican overdrive.

You will get many varying answers on the mileage depending on who you ask. You should not reset the overhead frequently if you want a more accurate assessment. Try letting it go for two or three thousand miles and then report back with the MPG.

In general the 06s are not getting the mileage that the previous model years are getting. It could be the three injection event thing. The G56 six shooter does have a higher numerically, lower final drive ratio than the autos or the older NV5600 equipped rigs.

Heck Grandma can't get 22 MPG on the highway driving my 03 like, well Grandma, even though the 03s reportedly get the best MPG of the Gen IIIs.

 

FYI.....21-22 highway is HAND CALC....The BS-O-METER has only been up to 16..And oh yeah..The '06 doesnt reset like previous years..Reseting on the downhill wont give you a better readout.........

Driving in town kills it..gets me 15...cold weather warm-ups REALLY kill it

Dont get me wrong...I havent gotten that mileage over the life of the truck....but station to station down the interstate gets me numbers in the 20's......

14.7 over the last 2000 miles

 

Pulling a #5000 TT 1000 miles I got 9.9 MPG at 65-70 MPH. Comiing back empty 13-14.5 MPG at 65-70 MPH. 7000 miles on truck after that trip. The route down was indiana to 70 west to 57south to Baton Rouge, LA, mostly hilly terrain. On the way back I had to cut across Tennesee to avoid the big ice storm in Arkansas and Missouri, then north up 65, some very long steep grades.

Oh yeah, my '06 overhead will read big numbers if reset going downhill, One of the big grades on I-40 in TN read 35 MPG.

By the way the mileage in the first paragragh were hand calculated.

 

Don't meant to offend anyone but you will get as many varying answers as the number of people you ask. The overhead on mine is very accurate except when it is reset going down hill in Mexican overdrive. There is little varyance between it and hand calculating. It is very hard to get the exact amount of fuel in the tank at each fill up. Don't forget to make an adjustment for oversize tires. You will not get an accurate result hand calculated or otherwise unless you make the adjustment. Also not all of the boxes are able to communicate properly with the overhead to calculate mileage. It usually will show much higher than what you are actually getting.

Anyone that gets 21-22 MPG highway on a 06 should consider themselves lucky. This is not the norm. In fact here at work a co-worker sitting right beside me just got his 06 4x4 dually about a month ago. The best he gets is 11-12 MPG combined city-highway and is not happy. And yes I know you are suppose to get better MPG after break in. I have now had two CTDs and neither one has shown a substantial gain after racking up the miles.

 

for me i am getting around 16 in the city, and 19-20 on the hwy hand calculated. just under 2000 miles.

 

Just bought a 06 2500 Mega Cab 4x4 with 11.5's. After a week and 650 miles I seem to be averaging about 18.5 to 19.0 overhead in mostly highway driving at 70 mph. I have not hand calc'ed it yet but I have found in my 2 previous rams that the overhead seems to be close. Within a mile or so. Mines always seems higher when done by hand. Your mileage sounds very low. You might take it to the dealer and get it checked.

Just my .02

 

My truck is at the dealer as we speak. I told him my actual problems and my concerns. We'll see what they say. I'm sure that at least one TSB is out for my specific truck maybe two. The highway shaking is my main concern. Tires/wheels have been checked and rechecked. The shaking only happens half of the time. Nothing like the described dw. My fingers are crossed. I do truly love the Cummins.

 

Hey, I'm down the road a minute in Belgrade. My 04.5 is currently getting in the 12's if I'm nice to it. Big difference in the winter blend. Each fillup with the winter blend I can see the difference. Your mileage isn't that out of line. The other thing you may want to seriously consider is running additives to your fuel. The winter blend around here is usually No. 1 and 2 mixed. No.1 doesn't have the lubricity that 2 has so I run Power service and MMO for every tank even in the summer. With summer fuel I can reach the 19's if I keep the RPM's under 2000 on cruise. Most of the time I run 80 at 2375 RPM's with stock 265's and get high 14's low 15's combined city interstate.

What is out of line is cutting in and out at speeds. You can check for codes by turning the key on and off three times without actually starting it. On the third time, it will either display some numbers in the odo window or the word done if there are noc codes. Once it shows either of those two it will go back to the odo reading.

 

My '06 is now a couple of weeks old, has 4000 miles or so on it, and is now in California, having towed an 8.5k trailer down here from Washington. Average mileage for this trip, hand calculated, is 11.2, with 9.8 on one section in the mountains.

Solo, so far, the truck has been getting about 18mpg, again always hand calculated - the trip computer is usually way off, but today, towing, it is spot on. I am down the mountains, on on the flat, so the mileage should go up..... hopefully.