View Poll Results: LB7 Duramax local driving fuel economy (55-65 mph)

Voters
1245. You may not vote on this poll
  • less than 15 mpg (US gallons) (55-65-mph)

    97 7.79%
  • 15-16 mpg

    251 20.16%
  • 17-18 mpg

    337 27.07%
  • 19-20 or more mpg

    376 30.20%
  • Don't own an LB7 - just interested in the poll data

    184 14.78%
Page 5 of 6 FirstFirst 123456 LastLast
Results 81 to 100 of 114

Thread: 2001-early 2004 LB7 Duramax Fuel Economy Poll

  1. #81
    Join Date
    Nov 2006
    Posts
    33

    Default

    1. MPG
      Mileage is constantly 22 or 23 on highway In town is20 or 21 4K miles #2 fuel Flying J Cheyene Wy.06 LBZ 4x4 Allison Reg. Cab
    Flow Pro Exhaust 4.5" Stainless EDM Fits

  2. #82
    Join Date
    Apr 2001
    Location
    CA
    Posts
    13,603

    Arrow

    Quote Originally Posted by colt49
    1. MPG
      Mileage is constantly 22 or 23 on highway In town is20 or 21 4K miles #2 fuel Flying J Cheyene Wy.06 LBZ 4x4 Allison Reg. Cab
    Flow Pro Exhaust 4.5" Stainless EDM Fits
    Those numbers are pretty impressive. Are you using any type of electronic power enhancer? Larger than OEM tires? How are you calculating your mileage? Pencil/calculator, or DIC?
    1985 Blazer 6.2
    2001 GMC 2500HD D/A
    dmaxmaverick@thedieselpage.com

  3. #83
    Join Date
    Nov 2006
    Posts
    33

    Default Mpg

    This truck is mostly stock exhaust is customed synthetic fluids except motor still breakin cycle on it. Very steady driving cruise control user and slow down and vary speed for break in. Will not install any turners or air intakes, stock is totally fine. This truck will be a good one it's just something you know when you start breaking it in and the power and strength it has. This is the smoothest tranny in the world to me. It downshifts at stops and you save brake use by tons. GM makes my truck and I'm glad I bought this one. The others are nice too buy this one is my vote. Price was real nice compared to the other guys by thousands and no intrest loan was even better. I've owned the other diesels since 93 Dodge Cummins, 96 Powerstroke, and now this one. The others sold for prime bucks because of diesel and they were ok to own but nobody on this planet has this GM setup. My right foot can take this thing to 100 mph fast it's nice to have.

  4. #84
    Join Date
    Aug 2006
    Posts
    15

    Default

    i recently switched to 285/75/16 and my mileage droped almost 2mpg. is that normal. also with 285's how off is the odometer. i heard almost 5%?

  5. #85
    Join Date
    Dec 2004
    Location
    Texas
    Posts
    683

    Thumbs up

    JUST COMPLETED THE CALCULATIIONS.
    100,278 MILES, 5,394.74 Gallons of fuel used, = 18.588 MPG average for the first 100.

    I knew that Edge was going to make it drop off!!
    Long live LB7's.
    02 2500HD LT D/A SB CC 4X4 BLACK, Westin stainless nerf bars, BW GN Hitch,Racor 60S post oem fuel filter, Oil Guard bypass engine oil Filter. All synthetic fluids. Kennedy boost valve, edge, Modified air intake,EGT & Boost digital gauge,TransferFlow combo fuel & tool box, Air Lift Suspesion Bags Rear & compressor with remote, Bilsteins front & rear, Frontier front replacement bumper.

  6. #86
    Join Date
    Sep 2006
    Location
    British Columbia
    Posts
    2

    Default ickyray

    The poll can be misleading, there are different axle ratios which will affect the mileage noted. I just pulled a 24 foot TT through the Rockies for 1400 miles and average 15mpg imperial. Kept to highway speeds plus 10 over, nobody was waiting for me! Truck has 3.73's and 4X4.

  7. #87
    Join Date
    Apr 2001
    Location
    CA
    Posts
    13,603

    Arrow

    Quote Originally Posted by ickyray
    The poll can be misleading, there are different axle ratios which will affect the mileage noted. I just pulled a 24 foot TT through the Rockies for 1400 miles and average 15mpg imperial. Kept to highway speeds plus 10 over, nobody was waiting for me! Truck has 3.73's and 4X4.


    All Duramax equipped light trucks are available with only the 3.73. Any other ratio would have to be owner installed. The 8.1L and 6.0L gassers have the option of 3.73 or 4.10. Tire size changes will effect mileage, though. 10 over with trailer in tow, and no paper trail??
    1985 Blazer 6.2
    2001 GMC 2500HD D/A
    dmaxmaverick@thedieselpage.com

  8. #88
    Join Date
    Dec 2004
    Location
    Texas
    Posts
    683

    Default

    Yesterday at the station I was adding my fuel supplement and started to pump diesel and two guys walking to their truck made a comment. That won't help it will still only get 13mpg. I glanced at his truck it was a chevy gasser.
    I told him I have an average of 18.58 for a 100, 000 miles now and not all of that is easy driving. I've towed some pretty heavy loads. He said oh, you got the Duramax, took a big gulp of his Coors Light and said come on Joe lets go.Got in his truck and drove off. I don't think he believed me, or else he was kicking himself for not driving a diesel.
    02 2500HD LT D/A SB CC 4X4 BLACK, Westin stainless nerf bars, BW GN Hitch,Racor 60S post oem fuel filter, Oil Guard bypass engine oil Filter. All synthetic fluids. Kennedy boost valve, edge, Modified air intake,EGT & Boost digital gauge,TransferFlow combo fuel & tool box, Air Lift Suspesion Bags Rear & compressor with remote, Bilsteins front & rear, Frontier front replacement bumper.

  9. #89
    Join Date
    Jan 2005
    Location
    Texas
    Posts
    1

    Cool

    2001 4x4 HD ext cab. 275 tires got 19 to 21 mpg. 200100 miles. Injector pump @ 25000m, water pump at 100,000m. just traded 3 weeks for a NBS GMC 6.0 gas 6-speed and traded yesterday for NBS DURAMAX.....Should have known better........but I'm old and allowed to make misteakes....
    Chevy-D

  10. #90
    Join Date
    Jul 2007
    Posts
    15

    Cool

    03 d/a 2500 reg cab , 4x4, 3.73s, 265s, 18 city stock, 23 highway stock, 16 city juiced level 2, 21-22 juiced highway level 2. Hand calculated. 70 to 75mph highway, mostly flat with some long grades here and there. Seems to get better highway mileage on the button rather than the pedal.

  11. #91
    Join Date
    Jan 2001
    Location
    Tampa, FL
    Posts
    382

    Default

    Long time since I last posted but after reading this thread again I had to post my recent milage record. Had to make a mad dash to WV (from FL) for the passing of my Father-in-Law just about a month ago. On the way up I didn't even bother. It was just one speed(as fast as I could get away with). But on the way back things were a little more relaxed I got 21 mpg in my 02 4x4 CrewCab dually that just turned over 160,000 miles (original injectors and bone stock). Now mind you I had nothing but the four of us and the luggage in the truck but it's wasn't too shabby for a 7000# tank. LOL







    David
    __________________
    Oneton
    2002 3500HD Pewter/lt grey interior Crew Cab 4x4 LT Durmax/Allison

  12. #92
    Join Date
    May 2007
    Location
    Hemet, Ca
    Posts
    77

    Default

    I added a Bully Dog downloader and set it on the 1 power level on the way to Phoenix from my home in Hemet. I ran 70-75 mph and got 18.5mpg. On the return trip, I changed the power level to 2. I got 21 mpg on that trip and 22 mpg on a subsequent trip, though I ran that one at around 65 mph. I was pleasantly surprised by this.
    Owner, Phil's Auto Clinic, Hemet, CA, 1997 Napa/ASE tech of the year

    2001 D/A Crew cab long bed, Edge Juice w/Attitude Monitor, Banks Exhaust, S&B intake, BD exhaust manifold, 152k miles, 2nd set of injectors 06/25/07

    2000 Powerstroke Ford Club cab short bed, Edge Juice w/Attitude Monitor, 5" exhaust, S&B intake

  13. #93
    Join Date
    Jul 2007
    Location
    Desert, near Pima Arizona
    Posts
    12

    Default 2001 4X2 GMC Crew Cab milage

    With 100K on my 2001 Duramax I have averaged 20mpg
    with no load, 15MPG with a 3000 lb truck camper, 10MPg with
    a 33 FT 5th wheel trailer. Interesting, recently I got new Cooper Tires, replaced my old Michelin's, Coopers lowered my mileage to 19???
    This is a stock truck except for the L&N air filter. Most of our driving is rural mountain areas.

    Jim T in Pima Arizona
    2001 2500HD Crew Cab:
    Full Bed

  14. #94
    Join Date
    Feb 2008
    Location
    Oklahoma
    Posts
    4

    Default

    I was getting 13 average. Did some research as I had a problem the dealer mech's couldn't find. Lead them to the fuel injector area and they found my injector pump had gone bad. Once this was fixed I got 18 average. Dropped from 15w-40 synthetic to 5w-30 synthetic for the winter and am now getting 19.5 average.

  15. #95
    Join Date
    Sep 2001
    Location
    Boise, Idaho, USA
    Posts
    54

    Default mileage

    I have been getting 16-18 around town and 20 highway on my '01.
    \'01 Chevy CC 4X4 SB D/A 40-20-40, bedrug, glass topper, carbon fiber look deflector, Luverne nerfs, Husky mats, majority pewter in color, auctioneer, sporting clays shooter, yadda yadda, thanks for listening

  16. #96

    Default LB7 mileage

    Mileage is greatly affected by driving conditions. I get 16-18 mpg driving in town stop and go. On the highway I get 20-23 mpg depending on speed. My best was towing a 6 ft utility trailer at ~ 50-55 mph descending from 8000 to 6000 feet in 200 miles; I got 23.2 mpg. Typical is 21-22 mpg at 60 mph decreasing to 19+ mpg at 70 mph.

    reparkerjr

  17. #97
    Join Date
    Mar 2008
    Location
    Peoria, IL
    Posts
    80

    Thumbs up So far so good

    I just bought my first diesel (see sig). The first full tank I ran was maybe 1/3 on the highway at 60, 1/3 in town, and 1/3 interstate at 70. I got 20.5 mpg!!!

    I'm thrilled with my LB7, especially since the miles/dollar work out to be only about 10% worse than my gas truck, despite being 3' longer, a bit taller, 4wd, and a good ton heavier.
    2002 LB7 2500 CC LB 4x4 80k
    6 spd, 3.73, 265's

  18. #98
    Join Date
    Jun 2008
    Location
    Ohio
    Posts
    19

    Smile

    I've owned a few trucks for my remodeling company. I had a 97 GMC 1500 Z71, an 88 chevy 1500 extended cab LB, a 92 GMC 3500 Vandura with 6.2L N/A, and my 01 Silverado. Hands down the two diesels were much better all the way around. I could easily get 450+ miles out of my van on the highway. I've just done the upgrades to my Silverado, so I don't know what the mileage is yet after the fact. Bottom line: WOOOHOOO for Clackers!
    '01 Silverado Std Cab/LB D/A 4x4
    -4" Straight Exhaust
    -Homemade $48 Intake
    -07-08 Telescoping Mirrors
    -285 Nitto Terra Graplers
    -Boss 7'6" HD Plow
    '90 Jeep Wrangler YJ w/ 6.2L NA
    '00 Harley Davidson FXDWG
    '73 Firebird Formula (90% resto'd)

  19. #99

    Thumbs up LB7 mileage

    My 2003 LB7 (3500 4x4 dually)with breathing enhancements(ram air and 4in exhaust) just did 2500 mile mostly freeway trip largely on cruise at 75mph for overall round trip average of 19.6mpg. Lightly loaded with about 1500# of gear in the bed. My mileage starts dropping rapidly at over 65mph....trips holding to 65mph have netted me typically about 24mpg. Love it!

  20. #100
    Join Date
    Dec 2008
    Location
    Indiana
    Posts
    15

    Default

    On a totally stock 2002 HD2500 Allison Ext Cab 4x4, all hand calculations, purchasing from the same station and pump, filling from 1/4 tank each time, using Stanadyne PF each fill up...I've come up with the following over the last 11 months.

    Highest 18.85 MPG.
    Lowest 16.90 MPG (I did alot of city driving this go-round and was a little heavy on the pedal at times)
    Furthest Distance from 4/4 to 1/4 tank (fill up point) = 392 miles (I do not go below 1/4 tank as a personal preference)
    19.878 gallons average purchased at fill up.
    Total overall average MPG = 18.01
    Average price per gallon = $2.629/gallon
    Total miles represented to produce this data in 11 months = 13,233 MI

    The truck has 142,000 miles on odometer, no modifications at all, original injectors, Mobil Delvac 1300, Mobil Syn gear lubes, Valvoline Dexron III ATF, Mobil1 5W-30 transfer case lube, OEM Bridgestone tires etc etc. About a 60/40 ratio of hwy vs. city driving. All empty miles, no towing. 65 MPH highway shows about 18-1900 RPM.

    So...unless new injectors and such would really improve MPG's...I don't see how people get anything significant over 20 MPG Avg. My friends claim to...but they have zero data to support the claims.

    Now keep in mind this is all average MPG's for me. Which is all I pay attention to. Because I'm buying diesel when my average driving empties the tank.
    2002 Chevrolet HD2500 4x4 LT
    Extended Cab - Shortbed
    Duramax LB7-Allison 1000
    Charcoal Metallic Ext/Int

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •