Diesel Truck MPG

One thing I've not seen mentioned is how many of you calibrate your odometer with GPS? I =know= I'm 4% under due to running 265 tires instead of the stock 245's, so whatever my odo says, I multiply by 104% to get a more true mileage.

Lyle

Cummins12V98 wrote:
When reporting Diesel or any miles per gallon it needs to be over several tanks and weather conditions then an honest "AVERAGE" can be determined.

I get as low as 7.5 with head winds and as high as 12 with tail winds but in all conditions I average 9.5mpg with 28K combined weight 2011 RAM Dually.

Same conditions over many tanks 98 RAM 2500 4X4 combined 20.5K 10.5 mpg. I could tell about the 13mpg tank with a tailwind and forget the others but these numbers are REALITY.

Oh yea fill the tank to the top each time helps. If not it can make a huge difference also if the truck sits out of level makes a difference how much fuel you can get in it. Lot's of factors to get a true average.

I have a 2004.5 Chev 2500 Duramax, and a 2011 Chev Duramax Dually. I share your thoughts on fuel mileage accuracy. Interestingly, I get almost exactly the same as you, including the difference between the 3/4 and 1 ton.

2011 F350 DRW 373 rear 10-11 puling the trailer 14900 lb.

Camper 2012 wrote:

whistlebritches wrote:
We averaged 13.5 mpg on a 2 week trip to Tennessee, Georgia, South and North Carolina last summer, pulling a 37' 5th wheel with a 2003 Silverado Duramax/diesel. At home solo, we get 22 mpg. I understand the newer Silverado's only get around 16-17 mpg. And this is diesel.

Is your truck 6.6 V8? Thanks.

You are right. Two weeks ago I purchased 2005 Chevy Silverado 2500 duramax diesel and we averaged 13.5 mpg pulling 26 ft. Fifth w.I love this truck. Thanks.

Traveled 12,600 miles 96 days doing National Parks. Many mountain roads and non-interstate routes. Ford F250 6.7 diesel Many variables involved averaged 12.4 mpg truck computer weas 12.6. I never exceded 65 MPH and used the manual mode with cruise primarily. From what I have read this is good mileage. All of todays diesels are good and competitive so pick the one you like.
Happy Trails Go Well

When reporting Diesel or any miles per gallon it needs to be over several tanks and weather conditions then an honest "AVERAGE" can be determined.

I get as low as 7.5 with head winds and as high as 12 with tail winds but in all conditions I average 9.5mpg with 28K combined weight 2011 RAM Dually.

Same conditions over many tanks 98 RAM 2500 4X4 combined 20.5K 10.5 mpg. I could tell about the 13mpg tank with a tailwind and forget the others but these numbers are REALITY.

Oh yea fill the tank to the top each time helps. If not it can make a huge difference also if the truck sits out of level makes a difference how much fuel you can get in it. Lot's of factors to get a true average.

On our trip from East Tenn to New Hampshire at the end of May we towed just over 1,900 miles per the EVIC. Hand calculated, I got 12.4 mpg trying to tow a steady 64 mph. On a CAT scale, the total rig weighed 19,600#. Coming up to TN from So Florida in April, towing my bike trailer with the bed loaded with the stuff we carry back and forth, I got a hand calculated 21.6 mpg at an average 69 mph.

This is my 3rd RAM and the best one by far.

Just got back from a 2,500 mile trip from Indiana to Cape Cod, and back home via Vermont. Most driving on interstates the exception of US 4 across Vermont through the Green Mountains. Averaged 11.4 with our 2007 Chevy 3500 SRW towing our 38 foot fiver weighing in at around 12,000 lbs. Didn't keep track of mileage when not towing, so no information there. Mileage on the westbound leg home would have been a lot better if we weren't running into sustained 25 mph winds coming out of the WSW.

I have a 2013 GMC 4x4 HD pulling a Coachman 29RKS about 6000 lbs fully loaded. I get about 15mpg pulling about 21 mpg without trailer. Awesome truck, sometimes I forget the trailer is back there, only irritating thing is the 5 gallons of DEF fluid lasts about 4000 miles before having to refill

My Diesel when not towing gets about 20 -22 mpg but it is the smaller Diesel from 2003, the diesels now are bigger so do not get the mileage we get AND a new diesel now requires an extra fluid that must be added every so many miles. Do not know the name of that fluid, it is something the diesel stations have available as I understand it but.. I was told I should upgrade the brakes to a heavy duty break that cools faster and get some stronger shocks but I love my 2003 Duramax Silverado 2500HD