05 chevy 2500 diesel mpg

[Knute]

you guys getting 15-17 mpg with your 3/4 tons make me sick i get 16 city(rarely ever drive highway, city is 90% of my driving) in my 2004 1/2 ton silverado Z71. granted i have 285 tires, but i had the computer reflashed for them. just cant seem to do any better then an average of 16. now i've done worse, about 15 a couple times. if i knew i could get a diesel 4x4 extended cab and KNOW it would get 17mpg i'd be doing alright. i could live with that.

Maybe this will make you feel a little better...I get 10.5mpg with my 94 2500 w/ the 454 gas engine. I only got about 13.5mpg in city driving my 2000 Suburban when I had 285/75/16's on it.

Now that diesel is coming down from the insane price it's been at I'm thinking that trading the pickup and Sub in for a crew cab diesel pickup might be a good idea.

 

[gemini5362]

THANKS FOR ALL THE GOOD ADVISE I WILL CHANGE THE AIR FILTER AND SEE WHAT HAPPENS.
AGAIN THANKS.

I had a 2005 dmax and got the same mileage as you are getting. I traded it in for a 2006 to get the 6 speed and now I am seeing about 18 or 19 once in a while if there are a lot of police on the highway and I am driving the speed limit I will see 20 to 21 there is a big difference in the rpms at 75 between the 5 speed and 6 speed allison. You can see some big differences in your mileage by just slowing down 10mph if you can do that.

 

[Soundguy]

Anyone know how to reset the fuel calculation on an 04 f250?

soundugy

 

[deere755]

I have an 04 2500 HD with a 6.0 gasser. I avg. around 12 10 if I am pulling anything at all and as low as 8.5 if I am pulling something heavy. We pulled our boat to Branson Mo. and got 8.5 mpg. 2 weeks ago I was forced to drive it on a short trip about a 100 miles away and back. I set the cruise at 58 and got 14. I checked it 3 times and I could not believe it. That is the absolute best it has ever done. I think my next one will probably be a diesel. I was planning on buying a diesel last time but good used ones were hard to find. I went to pull the trigger on one a couple years ago but I was just a day late. By this time I was tired of looking and needing a heavier truck right away so I bought a gas 2500HD. I like everything but the fuel mileage.

 

[jeffster]

My 06 LBZ (pre-DPF) gets about 13mpg around town and about 17mpg on the highway. Towing my 29ft travel trailer I get about 12mpg or so. Same with my other trailers. This is with BFG AT KOs at 265/75R16. It was almost the same with the stock 245s, btw. I love the truck and will keep it for quite a while for sure, but I wish it did get better mpg, considering there are a fair number of people that claim 20+.

My only other complaint is that GM interiors suck. I wish I could get my duramax/allison combo in a Ford shell. I absolutely love my friend's F350, I just wouldn't want the drivetrain.

 

[gemini5362]

My 06 LBZ (pre-DPF) gets about 13mpg around town and about 17mpg on the highway. Towing my 29ft travel trailer I get about 12mpg or so. Same with my other trailers. This is with BFG AT KOs at 265/75R16. It was almost the same with the stock 245s, btw. I love the truck and will keep it for quite a while for sure, but I wish it did get better mpg, considering there are a fair number of people that claim 20+.

My only other complaint is that GM interiors suck. I wish I could get my duramax/allison combo in a Ford shell. I absolutely love my friend's F350, I just wouldn't want the drivetrain.

I am getting a bit higher mileage than you are on non weight hauling. I usually see 18 to 19 if there are a lot of police officers on the highway I tend to see 20 to 21. I am sure that has nothing to do with the different rate of speed I drive when there are police around. I have found that people who are saying they are getting 20 + on an 2005 or newer duramax are either mistaken are are keeping the RPM's low when they take off and are driving around 70 MPH on the highway.

 

[john_bud]

I have found that people who are saying they are getting 20 + on an 2005 or newer duramax are either mistaken are are keeping the RPM's low when they take off and are driving around 70 MPH on the highway.

If you want better mpg's, drop your mph's. It's just that simple. Also, drive like a grey haired granny from the stops, plan your trips, do as much as you can to keep the truck temps up. A hot truck runs less fuel than a cold truck. A LOT less fuel.

I would say that if you want 20 mpg, drive on the freeway at 60.0 mph. You will get it.

jb

 

[GaryCrowell]

I have a 98.5 dodge with the 24 valve cummins and a five speed manual. It's a regular cab 2wd, the lightest combo you can get. Until diesel went out of sight it was my daily driver and it's now got 342K on the odometer. Over the life of the truck I've consistently gotten over 20 MPG highway out of it and most of that was driving 75-80 mph. I don't drive in the city much, not many of them around. When diesel got so high I started driving a honda civic for most things and only using the truck when I needed to haul something. A couple of weeks ago the civic was in the shop so I had to drive the truck all week. I wasn't in any particular hurry so I tooled around at 60-65 most of the time and got 22 mpg out of that tank. Slowing down in the easiest way to get better mileage but I know it's not always practical, if you're like me then your time is worth more than a few gallons of wasted diesel. Another thing that will really kill fuel mileage is bigger than stock tires. Are you running the stock size tires? I hear guys complaining about losing 3-4 mpg when they throw on the redneck tires.

 

[ronjhall]

I have a 2004 LLY in a C5500 Kodiak motorhome. Weight is over 23,000 lbs with car in tow. Mileage is just over 10 mpg. Keeping RPM's below 2000 is one of the items that saves a lot of fuel.
There are some relatively cheap upgrades that will improve fuel milage. I have done 3 of them with over 1 mpg increase in MPG.
EGR blocker plate.
PVC reroute.
Turbo inlet mouthpiece upgrade to LBZ.
The pickups could use some improvements in air filter and intake also. The Kodiak does not have this problem.
With the above upgrades my last 1000 mile calculations show over 11 mpg. A lot of improvement when hauling around this much weight.
Got most of my info from Diesel Place like others have suggested.
Seen on there modifying the exhaust will also help mpg. But on my Koidak there is a exhaust brake before cat and muffler. This limits any exhaust upgrade. Not about to give up the exhaust brake for a small gain in mpg.

 

[john_bud]

Ron,

I have asked about exhaust mods and mpg's. Just changing the pipes/mufflers makes it sound good, but no definite improvement in mpg.

There is a new-ish thread there on exhaust manifolds and up-pipe to the turbo that has shown lots of gain in turbo spool time as well as higher boost pressure. Might be a gain in mpg -> initial claims from a very small number of people claim to see about 1 mpg. But claim it's hard to keep the right foot light.

I hadn't seen the bit about the LBZ upgrade. Have to check into that.

jb