allgoods down fall - Diesel Truck Forum -
Thread Details Posted by allgood, this thread has received 12 replies and been viewed 1246 times.

LinkBack Thread Tools Display Modes
post #1 of 13 (permalink) Old 08-25-2009, 07:26 PM Thread Starter
Join Date: Aug 2009
Posts: 5
Points: 6,972
Thanks: 1
Thanked 0 Times in 0 Posts
allgoods down fall

i have a 2006 gmc lly thats getting piss poor milage on hyw when empty but loaded it gets better what can i do too change this so i dont have too be loaded all the time
allgood is offline  
Sponsored Links
post #2 of 13 (permalink) Old 08-25-2009, 07:34 PM
fordt's Avatar
Join Date: May 2005
Location: Vero Beach, FL.
Posts: 12,738
Points: 85,334
Thanks: 380
Thanked 1,064 Times in 566 Posts
Images: 5
First, Welcome to TDG!

Are you saying it get's better mileage loaded?

Is it bone stock? Stock tire size? What kind of mileage are you getting exactly? Hand calculated or from the DIC?

2007 Chevy LBZ 6.6L Classic

Age is a hell of a price to pay for maturity.
fordt is offline  
post #3 of 13 (permalink) Old 08-25-2009, 07:39 PM Thread Starter
Join Date: Aug 2009
Posts: 5
Points: 6,972
Thanks: 1
Thanked 0 Times in 0 Posts
allgoods down fall

sorry its got cold air 4 inch ext bully dog tuner after market tranny dont know what was done too tranny 33inch tires no lift i have about 145000 k on it and i have done both still dont know what too say
allgood is offline  
post #4 of 13 (permalink) Old 08-25-2009, 09:08 PM
'Ol Builder guy
Duke's Avatar
Join Date: Dec 2008
Posts: 7,051
Points: 121,352
Thanks: 340
Thanked 99 Times in 73 Posts
My guess would be be the tires. Oversize tires, especially those with knobby off road tread can take you down 1-2 MPG no problem.

All I did was switch to a mild off road tread on a stock size 265 and I lost about 1/2MPG.

The tuner could also be contributing. Take the tuner off for a few tankfulls and drive it the way you normally do and see if that increases fuel economy.

Check to make sure your tires are inflated properly.
Duke is offline  
post #5 of 13 (permalink) Old 08-26-2009, 05:01 AM
Senior Member
8yourv8's Avatar
Join Date: Dec 2008
Location: Alberta, CA
Posts: 499
Points: 25,389
Thanks: 5
Thanked 14 Times in 14 Posts
Terra AT type tires, Could there be something pluging up unless it has a load?

Driving 2007 Chevy LTZ CCSB LMM so far just EGR delete, Straight Pipe, ported fuel fitting, trans-go and PPE HOT RACE

SOLD SADLY 2004 F-350 CC SB 4Inch lift 35in tires on 20s 6.0lt EGR delete ported intake AFE stage 2 SCT Tuner ARP stud's back to stock injectors CFM Large mouth and 5" Magnaflow with 4"Down pipe 6" tip

8yourv8 is offline  
post #6 of 13 (permalink) Old 08-26-2009, 06:28 AM
Junior Member
DrHolliday's Avatar
Join Date: Feb 2008
Location: From Ohio, live in Havelock, NC
Posts: 182
Points: 20,261
Thanks: 6
Thanked 40 Times in 32 Posts
We need more info. 2500 or 3500, SRW or DRW? How fast do you drive empty and how fast do you drive when loaded? How much weight are you calling loaded?

What are the fuel mileage numbers you get empty and loaded? Are you going off the dash reading for mileage numbers or are you doing the math at every tank fill?

I'm running my truck, a 2500 ECSB SRW LBZ. Empty on the highway I can get 22+ MPG when keeping my speed under 70mph. If I go over 70mph the mileage drops drastically.

Loaded with 6-7,000 lbs (a car ona trailor) I can get 16-17 mpg at the same speeds, again if I go over 70 mpg it goes to *****.

Loaded with 13,000-14,000 lbs I can get 12-14 mpg depending on terrain, speed, etc.

2006 Chevy 2500HD LBZ/Allison ECSB 4x4 Greystone metallic

S475, 3" boost tubes, 5" intake, Custom Y-Bridge
Tuning and Transmission by Diesel Addiction . A special thanks to Dustin for all the help.

12.42 @ 106.3 (stock injectors, CP3, and turbo, no drugs!)
7.83 @ 86.2 1/8th
531 RWHP / 940 RWTQ 10/11/08 on Wayne's Dyno in Jville NC

USMC 2002-present
DrHolliday is offline  
The Following User Says Thank You to DrHolliday For this addition to TDG:
allgood (08-28-2009)
post #7 of 13 (permalink) Old 08-28-2009, 02:09 AM Thread Starter
Join Date: Aug 2009
Posts: 5
Points: 6,972
Thanks: 1
Thanked 0 Times in 0 Posts
mine is a 2500HD i get about 14mpg empty doing around 115k rpm is at 1600. load with car on a trailor and a slip tank full 450L i get about 22mpg and thats doin 115k over the same road all hyw
allgood is offline  
post #8 of 13 (permalink) Old 08-28-2009, 02:18 AM Thread Starter
Join Date: Aug 2009
Posts: 5
Points: 6,972
Thanks: 1
Thanked 0 Times in 0 Posts
i did buy the truck used with 65000k it look like it had a welder in the back at one time it runs strong i think theres more done to it that i dont know about
allgood is offline  
post #9 of 13 (permalink) Old 08-28-2009, 03:31 AM Thread Starter
Join Date: Aug 2009
Posts: 5
Points: 6,972
Thanks: 1
Thanked 0 Times in 0 Posts
im also wondering if my injectors are working better when the motor runs warmer loaded do anyone think i might have too change them if so too what stock or bigger?
allgood is offline  
post #10 of 13 (permalink) Old 08-28-2009, 11:44 PM
BriteWhiteRam's Avatar
Join Date: Oct 2006
Location: Alberta, Canada
Posts: 4,320
Points: 63,250
Thanks: 350
Thanked 506 Times in 416 Posts
i cant see how your getting 22 with a load, im not even getting 20 empty, pulling a boat i get 17..... thats just a little boat!!!!!!! so i think something is a little fishy here

Aaron the Crazy Canuck
2006 Chevrolet Silverado LT 2500: LBZ - Allison, Greystone Metallic, 4x4,PPE airbox mod, missing muffler/cat, EFILive tuned by Nick at duramaxtuner, MA tie-rod sleeves and Grade C headgaskets
Totalled!! May 2nd 2008-2005 Dodge Ram 3500 laramie: Cummins auto, plain white, rebuilt tranny
1986 Mercury Capri - 5.0L, AOD, shorty headers, acell ignition, Holly street dominator intake, Holly 625 vacuum secondaries carb, Dual glass packs "my little yellow terror"

DURAMAX INDEX; You want a Duramax? you want to click on this >>The Duramax Index

Canadian Club Member #1
Singles Club member #186
Ridin Dirty Club #5


Check out the NEW and IMPROVED TDG Truck Poll!
BriteWhiteRam is offline  

Quick Reply

Register Now

In order to be able to post messages on the Diesel Truck Forum - forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

Similar Threads
Thread Thread Starter Forum Replies Last Post
Fall pics Sledpuller500 Boating 5 12-28-2008 11:07 PM
6.7 takes a fall. HD_F250 Road Kill, Bench Racing 249 05-02-2008 02:39 AM
Fall Smokin?????? wastedwagesracing Events and Gatherings 29 08-24-2007 12:05 AM
Touareg TDI available this fall.?! TooMuchBoost Euro-Diesels 0 03-20-2006 06:10 PM
Fall break adrianspeeder The Parking Lot 5 10-25-2005 05:15 PM

Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome