mpg in the tolet

mil_one_lion · August 14, 2004

I have A 2004 2500HD duramax 6.6 V8 was getting 16.9 mpg had a service done at 3000mi then the mpg droped off to 11.5 the dillership told me this was within the realm and threr is nothing wrong with it .

Is this right ? every one that i talk to about the fuel mileage tell me they are getting 18 and above .

The qestion is who is blowing smoke ?

MCourson · August 15, 2004

If it dropped off after they worked on it I'd raise hell.

Also, the dmax fuel mileage gets better as it gets broken in. I have seen 23mpg on a highway trip and usually get 19-20 mixed driving.

Edit, 42,000 miles here 2003 LB7 Dmax/Ally

Edit again, Welcome to the site.

BlackSilver · August 15, 2004

Is that actual calculated mileage, or what the DIC is telling you? The DIC is notoriously inaccurate.

Mine (with 45,000 miles on it) gets better than 12MPG pulling over 6-tons of camper trailer so your 11.5 empty is NOT OK!

neat · August 19, 2004

04 8.1 here with a 6 speed. 14 is the best I can do, you should easily best that with a 6.0 litre.

Wingnut · August 19, 2004

I don't know...6.0 liter is working harder to pull that heavy rig around.

Heck my 5.3 in a 1/2 ton usually only gets about 13.5 mpg. in mixed driving.

SOM Truck · August 19, 2004

Why are guys referring to gaser engines? (6.0 and 5.3) It's a 6.6 Duramax.

And NO that mileage is not acceptable. Most people pulling BIG loads still see 11-12 mpg.

Machine · August 20, 2004

I've been getting 11-12 while pulling a load. That kind of mpg while running around empty clearly indicates that something is wrong. How many tanks of diesel have you gone through with this kind of mpg?

Hecktorx · August 20, 2004

Heck my 5.3 in a 1/2 ton usually only gets about 13.5 mpg. in mixed driving.

Wow, that's bad or you have a heavy foot. Is that while towing? I get about 17mpg. The difference couldn't be that much different between a reg cab and an x-cab.

jt1quik86 · September 14, 2004

My 2005 2500HD Duramax/Ally 4X4 seems to get 13-16 in town. This weekend I pulled my 10000 lb boat and was a little dissappointed. Mileage averaged 9-10 mpg at 60 and dropped down to 7.7 - 7.8 mpg at 68-71 mph, I was expecting better. What do you all think?

whitesnake01 · September 14, 2004

My 2005 2500HD Duramax/Ally 4X4 seems to get 13-16 in town. This weekend I pulled my 10000 lb boat and was a little dissappointed. Mileage averaged 9-10 mpg at 60 and dropped down to 7.7 - 7.8 mpg at 68-71 mph, I was expecting better. What do you all think?

<{POST_SNAPBACK}>

We're up to 1,200 miles on our 2005 2500HD LLY/AT/4x4. We're getting about 20mpg on the highway (calculated) and about 14mpg towing an 8,300lbs trailer. I am quite happy about that. My trailer is quite aerodynamic (looks like a silver hot-dog, if you know what I mean). I drive near sea level. The terrain is mostly flat, with slight rolling hills in some places. My first impression is that the DIC shows slightly below actual mpg if solo and a bit above when towing. My 454 gets about 14mpg solo on hi-way and about 9mpg towing. But I can certainly get the 454 down to 7mpg if take on real mountains.

TPB · September 14, 2004

My 2005 2500HD Duramax/Ally 4X4 seems to get 13-16 in town. This weekend I pulled my 10000 lb boat and was a little dissappointed. Mileage averaged 9-10 mpg at 60 and dropped down to 7.7 - 7.8 mpg at 68-71 mph, I was expecting better. What do you all think?

<{POST_SNAPBACK}>

My 2005 GMC w/ Duramax is getting nearly identical mileage to your '05 Chevy. I get 13-14 in town; Highway unloaded - 17; Pulling my 8,500lb fifth wheel at 65mph I got 7.5. I was expecting a bit more.