2001-early 2004 LB7 Duramax Fuel Economy Poll

[goodmonkey]

Unfortionatly I'm within city limits and not far from work, so I average 20 city miles daily back and forth in my 2001 Silverado. So that puts me somewhere about 13 mpg. Over the highway though I get between 17.5 and 19, traveling at 70 MPH. I'm sure the camper shell is helping cut into that. But for the size of the vehicle it really isn't bad.

[EZ39e]

2001 3/4 ton, 19 combined 25 highway. These are documented from 0 miles to over 100,000. Highway speed is 70 MPH.

[Cracker65]

With 34,500 miles on the odometer, and towing a 8,400 pound Airstream trailer, I'm getting 13.7 mpg in hilly country at 65 mph and about 14.7 mpg on the level. Solo, I get about 19.1 mpg at 65 mph on the level and about 16.8 in the hills. Around town (---mostly level,) I average about 14.5 mpg running solo. The truck has a hard fiberglass tonneau with a normal 500 lb cargo load in the bed - for an all-up weight of 8,400 pounds (---same as trailer.) These numbers all go down about 1.5 mpg using winter fuel blends in Maine.

2003 GMC 3500 Duramax CC, LB, 4WD

[Driveshaft]

I JUST RECENTLY DID SOME MILEAGE CHECKING. EMPTY WEIGHT IS 7000 LBS. GOT 18.7 MPG CRUISING AT 65 TO 74 MPH. TOWING EMPTY 4000 LB. TRAILER GOT 14.3 MPG, LOADED WITH APPROX 4000 LB. JOHN DEERE TRACTOR, 11.7 MPG. COMBINED TOWING SAME TRAILER LOADED AND EMPTY WAS AN EVEN 13 MPG. THIS WAS DONE OVER APPROX. 600 MILES. TRUCK IS STOCK WITH SWISS CHEESE AIR BOX. ALL HILLY AND FLAT GROUND. TRUCK IS '01 2500 WITH DURAMAX/ALLY COMBO. SPEED WITH LOAD WAS AGAIN 65 TO 74 MPH.

[Driveshaft]

ALSO, FORGOT TO ADD THAT MOST WAS WITH CRUISE CONTROL ON. WHEN TRANNY STARTED DOWNSHIFTING ON HILLS I TURNED OFF CRUISE AND DROVE WITH FOOT AND IT DID NOT DOWN WHEN I WATCHED MY SPEED, WOULD BE DOING AROUND 74,75 AT BOTTOM OF HILLS AND AROUND 66 TO 70 AT TOP.

[canucktravellers]

Towing Yes No
US MPG 12.53 16.56
Cdn.MPG 15.05 19.88
L / 100 Kms 18.75 14.19

1.) Done over 50,000 Kms, over two years.
2.) Tires changed to 265 and Speedometer out by 5% ie under running by 5%
3.) 160 Fillups.
4.) Traveled all over eastern Canada, Florida, Texas.
5.) Towing a 37 foot Titanium Fifth Wheel.
6.) Truck is an Extended Cab with a RETRAX Tonneau & Stock Tailgate.
7.) Fifth Wheel weighs 11,400 Lbs.
8.) GCW is 18,400 Lbs

[Cranke578]

Hi I have a 2002 3500 4 wheel drive crew cab dually stock with edge jucie set at 90 hp. I get aprox 440 miles per tank before the feed me light comes on (30 gal.)empty town/city driving or 13 mpg. I tow a 36 ft gooseneck race trailer and get aprox 10 mpg consistanly. I do not baby it and I drive & tow at 70mph.

I have been disapointed in the milage until I see other Duallys in the same "ballpark". Those extra tires and wider areo do hurt rolling resistace.

[BobNelson]

82,000 miles now on six tires, and overall with fairly meticulous records, I have 13.85 mpg. With the camper on and toy box behind, seems like the average is about 11. Best recorded hwy empty is 18.2, but generally about 15.5

[Mark Pearce]

Lead foot Average.
75 MPH Highway
Almost legal around town
Avg 15.5 MPG
All Unladen.

[Olden_B]

I have been amazed by those who post that they are getting better than 15MPG highway or other. I currently own two 6600 durmax's 2004 models, in silverado package Z-71 4X4 crew cab/short box 2500. Both have recently been put through the 30,000 mi program, at a cost of $700 per vehicle. NEITHER of my trucks which are almost exclusively driven on the highway get better than 13.5 almost always 12mpg. with cruise control on at 70. Does anybody have a clue why they are both getting such poor fuel economy. My local dealer has put them both on the computer, replaced the fuel regulator on one and the injectors on the other and still there has been no improvement, and an actual reduction in performance of the other. HELP??
Thanks!
Bill

Originally posted by 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

[redrider#1]

Olden, I am in the same boat as you. I just purchased a 2004 Silverado, D/A, crew cab, 4x4, long box and even though I have put few miles on it, I am getting nowhere near the mpg that everyone else has been reporting. So far I have been getting about 13-14mpg totally unloaded highway miles at 75mph. As I have a broken leg right now I have not been able to investigate further(air filter, fuel filter, etc.) What gives?

[Mudflap]

Around town I can't keep my foot out of it 15-16 mpg tops. On the road I set the cruise between 1800 and 2000 rpm 19-20 mpg all day, drops off a little in the mountains. 107,000 miles

[FireMedic]

Received Truck Dec 9, 2000 7 miles on OD
As of 7/15/05:
Mileage: 93,262
Hours: 2704.6
MPG Average: 16.6
(SF Bay Area Commute Traffic Range from 15.6 - 19.0)
Best Tank: 22.0 Road trip on cruise at 69mph

[hotwelder5]

names tony
I have a 2003 2500 with the edge extreme ,6"lift 35" tires 4" magnaflow exhaust & K&N filter & in town i get about 18 & 21 on freeway at 80mph, Im a happy camper, also 16mph towing my 21 foot boat up hill.Again very happy

[dmaxster]

with 124,075 on it I get an average of 19.2-20 hwy if I taker easy....driving around 60. at 70 i get 18.5 and city hwy I get 17.9 .... all and all I am really pleased. when I towed my buddy's gooseneck we weight GCVW 22,500 LBS then I was getting around 12 maybe 10 if Windy and Hilly but usually 12 MPG. All I can Say is SMILE EVERYTIME I start this BABY !!!!!

[chrisinkanata]

With very conservative driving i.e. 100-105km/h (62-65mph) unloaded over long distance consistently 26.5-26.9 Imperial mpg (22.4 US mpg). I have repeated this many times in the warm summer months with the stock 245's. BTW...speedo out by 2-3 mph according to my GPS. Understandable though since the tires are almost done and will be replaced over the winter while the snows are on the truck.

Towing - 7000lbs travel trailer (truck has a cap tapered up towards the rear and acts as a very good windbreak) ---- again very conservative driving and 18.3 to 19 Imperial mpg depending on terrain. (15.2 US mpg).

City summer driving same as towing.

I do notice that when I put the snows on (265's) the milaege takes a substantial hit. Empty hwy falls to 21-22 Cdn (17.5 US mpg). Two parts to that I think....larger tires (I use the GPS to record distance, not the odometer) and far colder temps. I wanted to replace the 245 summer tires with 265's but don't think I will based on that difference. I should put the snows on now while it's still fairly warm and see what the mileage is like.

Chris

[AlaskaDmax]

2002 CC/LB
Best HWy --- 21mpg normal is 19.5 to 20.
Day to day driving is about 22 miles each way, half hwy at 80 mph and half city stop and go = 16.5 to 17 mpg. I get 540 miles out of a tank if I push it to fumes on an average tank. I drive like an idiot, hard acceleration (2800 - 3000 rpm)from almost every red light. I have tried to keep it under 2000 rpms for a full tank, just to see what kind of economy I could get but I can't do it...I am too weak.
Lowest I've ever seen is 14 mpg on the Hwy...bro in law was drafting me through Nebraska...he said it was the best mileage he ever got!!!!!

[mhagie]

Bought truck last saturday(10/29/05)in central Indiana drove it home to SE Iowa 439mi @ 19.4 mpg
Not going to complain.
Merle

[TRPSHOOT]

Alright this isn't scientific or anything but this is what I came up with. I just drove from near Indianapolis to near Gunnison, Colorado for our annual elk trip. I reset the computer stuff to zero on the personal trip option (DIC).

I have 22,000 miles on my extended cab 2003 with 265 tires.

I weighed the truck empty and with trailer, full tank of fuel each time.

Truck weight with tool box, full tank of fuel, and no people= 6700 pounds.

We ran about 66 mph out there and according to receipts and old fashion math that = 17 mpg. Oh yal the utility trailer is a dual axle that we stuffed 3 quads on with other junk for a weight of 5200 pounds loaded.

Total round trip= 2634 miles

computer says = 14.0 mpg average

receipts and my math say = 14.8 mpg

average mph = 48

computer says 188.3 gallons used

receipts say 190.5 gallons used

There were about 10 times in Kansas that we were bored and kept the spedometer on 60 mph and then started the timer at the mile marker, consistantly we were at about 58 - 59 seconds. So if the spedometer is not already calibrated for 265 tires, then it is pretty darned close.

We were camped at 10,000 feet so says the GPS units we had. I took the truck back on some pretty rough 2 track trails with some really steep hills. The DMAX never missed a beat and I love that allison how it holds it's gear going down severe grades and hills.

The only thing was that when I first started the DMAX in the morning, it would smoke until engine warm up. I don't know if this is a faulty glow plug or what. Temp was around 19 degrees before sunrise. No smoke after engine operating temp was obtained.

The tranny temp stayed below 200 the whole time with the exception of the last 5 miles of the trip going up some really steep 2- track trails pulling the trailer.

This is a stock truck.

I am thrilled with the performance of this truck.

P.S. The Ford 10 cylinder gasser that accompanied us, got 8 mpg towing a 1700 pound pop-up camper.

[sjd_sd]

My mileage ranges from about 16 to 20. 16 happens with lots of 4wd use, deep snow and slow driving. 20 happens at a steady 65-70mph on the highway. I have a camper shell and one-size-up from stock tires. The price of diesel makes me wonder if it was worth it. Fuel for a gas-burner is about 40 cents less locally, so its almost a wash.