2001-early 2004 LB7 Duramax Fuel Economy Poll

[More Power]

Fuel economy is one of the top 2-3 reasons why most people buy a diesel pickup.

What we want to do here is help determine what people are seeing for non-towing fuel economy in actual on-road use.

Let us know what your truck delivers.... This poll is for owners of the LB7 (2001-early 2004 model Duramax 6600 engines). We are assuming summer blend fuel.

You will need to vote before viewing the poll data. If you don't own an LB7, but would like to see the poll data, you'll need to first vote in the poll using the "Don't Own an LB7" selection for both the local driving and highway driving sections.

Round your fuel economy averages to the nearest whole number. For example a 16.4-mpg would be 16, a 16.8-mpg would be 17.

MP

[ 01-03-2005, 02:32 PM: Message edited by: More Power ]

[Kennedy]

I placed my numbers in the 15-16 off hwy, and 17-18 on hwy, but in reality, I run near 17 off hwy, and near 19 on hwy pretty consistently. I'm seldom down to 16 off hwy, and seldom in the low 18's hwy. Just did not feel that I quite made the next brackets...

[BobW]

More Power,
How about a second poll on mileage while towing. Might break it up into weight ranges.

[More Power]

Weight, wind drag and speed introduce a lot of variables when towing.... It'd be tough asking the right poll questions that would include all of the possibilities.

Open to suggestions....

MP

[Pfouts1001]

MP, it might be good to run a 3 different polls for trailering, one for pulling gooseneck and tag open trailers (utility trailers, machinery trailers, and open car haulers), enclosed tag trailers (car haulers and rv trailers), and gooseneck/fifthweel enclosed trailers (Car haulers and rv trailers)... and then in each class break down into weight ranges ie.

gooseneck and tag open trailers
3K and under
3-6K
6-10K
10-14K
14K and up

Enclosed tag trailers
3K and under
3-6K
6-10K
10-14K
14K and up

Enclosed gooseneck/fifthweel trailers
7-10K
10-14K
14K and up

additionally, give the respondents an opt out for each weight category as you have done on this poll so that people may just view the post. This will allow people to respond to the weights which they most pull

just my 2 cents

[More Power]

What towing speeds?

MP

[BobW]

45-55 mph
55-65 mph
65-75 mph

[Foley]

I hope I see 19-20 MPG some day out of my truck. Be curious to know how many of the 19-20 range are stock and how many of those are 6 speeds.

[Todd Manning]

I just did an extended highway trip and purposely drove between 55-60mph the whole distance to check my mileage. Ended up getting 23 mpg (Imperial gallons), so this 19 mpg US (assuming my math is right).

2003 LB7 D/A with Magnaflow 4" exhaust and K&N air filter.

[Todd Manning]

I just did an extended highway trip and purposely drove between 55-60mph the whole distance to check my mileage. Ended up getting 23 mpg (Imperial gallons), so this 19 mpg US (assuming my math is right).

2003 LB7 D/A with Magnaflow 4" exhaust and K&N air filter.

[TMS]

Over the first 10,000 miles I could only get around 14-16. At about 10,000, everything seemed to run "free'er"....most recently a interstate trip back from Kansas in August running at 75+ returned 20-21 MPG !!! [img]smile.gif[/img]

[More Power]

gooseneck and tag open trailers
3K and under
3-6K
6-10K
10-14K
14K and up

Enclosed tag trailers
3K and under
3-6K
6-10K
10-14K
14K and up

Enclosed gooseneck/fifthweel trailers
7-10K
10-14K
14K and up

45-55 mph
55-65 mph
65-75 mph

That's 39 polling questions, not counting the fuel economy range and "does not apply" selections for each weight/speed category.

MP

[precision37]

Total miles driven in 2004- 17,811
Total fuel used- 825.408 gallons
21.58 mpg average for the year. No complaints.
2002 GMC reg cab,4X4, ZF, stock. Very light towing and some snow plowing.

[Scott Glewwe]

I have noticed one thing not mentioned in the poll. In the summer months I typically get an average MPG (60% highway) of 17-18. However wintertime sees this drop considerably to the 14-15 MPG range. I assume this is due to the greater amount of "cold weather additive" used to keep diesel moving in the cold weather. Unfortunately for diesel owners here, Diesel is also at its highest price during the winter (competing with the fuel oil market). No big deal but my old 6.5L chevy never saw this big a drop summer to winter.

[precision37]

It's a combination of winter fuel and cold temps. The engine doesn't run a top efficiency until it gets up to opperating temp.
Cold weather slows this process down a lot. Sometimes if it is really cold, my truck never even gets over 180 degrees unless I'm on the highway for awhile. Don't forget about having to turn gears and driveline components in cold lube fluids.

[Jim Brzozowski]

Worst mileage recorded, 11.73mpg, gooseneck loaded GCVW=24,500.Best recorded 20.73.Running empty@ 68 mph.

Overall Average-49,005 miles, 2,736.93 Gallons=17.9 MPG. in 1101.1 hours=44.505 MPH lifetime average so far. I'm surprised it's that high. I did 453 offroad miles Hunting in Colorado, some it crawling through the canyons in 4 low. It ain't my old K3500 dully, but I sure like the fuel mileage better.

[Kirkes]

I would like to know how you can get over 17 mpg? I have never got more than 16.5 weather I baby it or not.

[Corwin]

17 to 20 most common

Check out results on this link below question (12), results of 61 people from 2001 to 2003 Chev/GMC owners

http://hobbycanada.qazam.com/Surv/Ch...to%202003.html

[c5dura]

I can't believe the excellent milage you guys are getting. I got 37k on my truck and have NEVER been able to go 400 miles on a tank. Therefore, I have never seen even 13mpg.

Dealer tells me that is perfectly normaly for a big truck like mine (see sig). Are there any other 3500 4x4 guys out there that have been able to break 400 miles on a tank full?

[Inspector]

I have a little over 17K on the clock now and solo average about 14.5 to 15. Never have seen much better than that on the average. I do have J/A installed so that may be skewing the numbers. Towing my heavy rig the milage will be between 9.5 and 11.5. I never drive over 70 with the fiver.
Denny