LLY mpg? - Chevy and GMC Duramax Diesel Forum
04.5-05 LLY Duramax Powertrain Discussion of components that are directly involved in the power production and all that is needed to get and keep the truck moving . Engine , Transmission Ect

DuramaxForum.com is the premier Chevy and GMC Duramax Diesel Forum on the internet. Registered Users do not see the above ads.
Reply
 
LinkBack Thread Tools Display Modes
Old 07-03-2012, 04:21 PM   eBay Motors  #1 (permalink)
Junior Member
 
Join Date: Apr 2009
Location: MN
Posts: 143
Angry LLY mpg?

Just got back from a 1st time, 1000 mile camping trip in my lly and expected better mpg when comparing it to my lmm. Had a pickup box camper, small boat, and gear I estimate at around 5200 lbs. Seen 11.3 mpg on the way there, and 12.2 on the way home. Iíve ran this exact same trip (several times in the past) with my lmm with 5th wheel, larger boat, more gear I estimate at 9800 lbs. and never seen anything under 10.8 mpg to 11.6. Both trucks run 50 hp efi live tow tunes. Iíd run the lmm in manual 5th gear, th on, and the lly in 5th gear and th on. Same speed 60-63 mph. I guess being 4000+ lbs lighter I was expecting 13-14mpg. Is this just an lly thing? Or should I be looking into something? In my mind it just donít add up. I over maintenance everything so I donít know where to start. I feel a 6.0 gas would have pulled them #ís. I should add, I see good #ís when empty. 19-20.5 at 60mph.
__________________
09 Silverado K3500 LT CC SRW, 4" MBRP TB muffler only, EFI Live 50hp tow tune, EGR Block, stock tires.

04 LLY Silverado K2500 LS Reg cab, 4" straight MBRP TB, EFI Live DSP2 50 hp tow tune, econ tune, EGR Block, AFE mp, tires upped to 265/75 r16.
BGD-09DM is offline   Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Old 07-03-2012, 04:24 PM   eBay Motors  #2 (permalink)
DuramaxForum Veteran
 
primetime_2's Avatar
 
Join Date: Sep 2011
Location: WI
Posts: 1,072
were you fightin the wind at all?
__________________
-2012 DENALI 1500

-2006 GMC CCSB LBZ --Sold--

http://performancetruckproducts.com/

-2004 Grand Prix GTP
Stocker

-2008 Pearl White Streetglide
primetime_2 is offline   Reply With Quote Quick reply to this message
Old 07-03-2012, 04:59 PM   eBay Motors  #3 (permalink)
Junior Member
 
Join Date: Apr 2009
Location: MN
Posts: 143
Quote:
Originally Posted by primetime_2 View Post
were you fightin the wind at all?
Not alot. Way up was just about nothing. Way home had maybe 10-15 out of the west but 80% of the trip runs north to south.
__________________
09 Silverado K3500 LT CC SRW, 4" MBRP TB muffler only, EFI Live 50hp tow tune, EGR Block, stock tires.

04 LLY Silverado K2500 LS Reg cab, 4" straight MBRP TB, EFI Live DSP2 50 hp tow tune, econ tune, EGR Block, AFE mp, tires upped to 265/75 r16.
BGD-09DM is offline   Reply With Quote Quick reply to this message
Old 07-05-2012, 12:56 PM   eBay Motors  #4 (permalink)
Junior Member
 
Join Date: May 2012
Posts: 37
15 litres per 100KM in town
12 on the highway


around 20mpg
LLY- is offline   Reply With Quote Quick reply to this message
Old 07-05-2012, 01:15 PM   eBay Motors  #5 (permalink)
DuramaxForum Enthusiast
 
rd05lly's Avatar
 
Join Date: Mar 2011
Location: Missouri
Posts: 2,020
What are the tire pressures? I have never got the bad of fuel mileage in my lly 14 is as low as I get towing.
__________________
05 CCSB EFI Live by Kory
2011 Chevy Tahoe
04 Olds Alero DD
76 Dodge Charger SE
87 Chevy Silverado
https://www.syntheticmotorsports.com
rd05lly is offline   Reply With Quote Quick reply to this message
Old 07-05-2012, 01:38 PM   eBay Motors  #6 (permalink)
Super Moderator
 
jc1843's Avatar
 
Join Date: Jun 2008
Location: So. Cal
Posts: 11,878
How fast were you driving-- speed affect the MPG a lot!

Did you hand caculate the numbers? Or use the DIC-?
__________________
Chevy 04.5 LLY, 2X, shell, XDR, MikeL Heavy duty up-grade, 6spd, TransGo, deep pan, de-badged, 65 Gallon replacement Aero tank, LBZ-mp, Kennedy pump, shimmed, Pre-fuel filter, tow mirrors, BU cam, gauges, GPS, Sirius, bags, custom grille, fender vents, HD trans cooler- Curt front hitch, footwell lights, load lights, Studs, head gaskets.--- Jerry
jc1843 is offline   Reply With Quote Quick reply to this message
Old 07-05-2012, 06:17 PM   eBay Motors  #7 (permalink)
Junior Member
 
Join Date: Apr 2009
Location: MN
Posts: 143
Quote:
Originally Posted by rd05lly View Post
What are the tire pressures? I have never got the bad of fuel mileage in my lly 14 is as low as I get towing.
And with only 5000 lbs that is what I was expecting. I had them maxed out at 80 psi. Can I ask how much weight do you tow? Speed? Thanks

Quote:
Originally Posted by jc1843 View Post
How fast were you driving-- speed affect the MPG a lot!

Did you hand caculate the numbers? Or use the DIC-?
I donít care to give our state law enforcement any money so I never go over 62-63 mph. But at that speed it is running around 1900 rpm. Is that rpm starting to kill mpg? I need to run the lmm down the road again, but I think in manual and 5th gear, Iím running the same rpm. All figures were hand calculated.

This might be worth mentioning. Iím no expert on aerodynamics but the front of the camper is completely flat. ( bunks above the cab) Which measures 7í x 3í. Could I be loosing 2-3 mpg over that?
__________________
09 Silverado K3500 LT CC SRW, 4" MBRP TB muffler only, EFI Live 50hp tow tune, EGR Block, stock tires.

04 LLY Silverado K2500 LS Reg cab, 4" straight MBRP TB, EFI Live DSP2 50 hp tow tune, econ tune, EGR Block, AFE mp, tires upped to 265/75 r16.
BGD-09DM is offline   Reply With Quote Quick reply to this message
Old 07-05-2012, 07:08 PM   eBay Motors  #8 (permalink)
Junior Member
 
Join Date: Jun 2011
Posts: 33
I average 15.5-16.0 mpg combined (in town/limited highway), 20-22 mpg highway (avg. 65 mph/empty), but it quickly drops to 9-10 mpg when towing my 36' WW (60-65 mph/14K-15K trailer weight). With what you were towing, I'd expect to get 13-15 mpg easy, but towing mileage seems to be a strange beast. I've read some threads where owners claim roughly the same mileage regardless of what they're towing...
__________________
2005 CCSB LLY
AFE mouthpiece
Airbox mod
MBRP 4" cat back
Firestone airbags
Curt R16 5th wheel
CTS Insight
olddudesrule is offline   Reply With Quote Quick reply to this message
Old 07-05-2012, 08:00 PM   eBay Motors  #9 (permalink)
Duramax Forum Supporter
Supporting Member
 
DMaxxrus's Avatar
 
Join Date: Feb 2011
Posts: 1,547
Do the lbz mp and egr delete. You will see 2 mpg right there...well atleast i did.
DMaxxrus is offline   Reply With Quote Quick reply to this message
Old 07-05-2012, 09:08 PM   eBay Motors  #10 (permalink)
dat lly doe
 
chevylovinfordtech's Avatar
 
Join Date: Mar 2012
Location: Fortuna, CA
Posts: 3,568
Quote:
Originally Posted by DMaxxrus View Post
Do the lbz mp and egr delete. You will see 2 mpg right there...well atleast i did.
his sig. already says hes got a delete, but x2 on the mouth piece, and if u havent already done it lose the kitty!!!
__________________
-Robert-
2005 CCSB Silverado 2500 HD LLY
Performance: LBZ Mac performance intake, LBZ mouthpiece, MBRP duals, shim kit, ported fuel rail fittings, headstuds, FASS150, FASS fuel filter delete bowl, LBZ FPR, EFI live by Idaho Rob
Air Flow:finger vanes, ported turbine housing, BatMoWheel, losend unison ring, ported exhaust manifolds, gasket matched up-pipes
Exterior: Rear Reunel bumper, leveled tow mirrors, HIDs (all on mod), ADP tie-rod sleeves, green tinted headlamp housings
Interior: 2 12" memphis car audio subs, custom sealed box and 2000 watt memphis amp, LED interior, dash and door lights-green, cobalt autometer pyro and boost piller gauges
Best Time: 13.92 @ 95 mph 1.96 60 foot
Work In Progress: 1969 Chevy Nova, built turbo 350, 283ci small block est. 550hp with 7500 rpm redline, caltracs, 4.11 ford 9" rear end, dual 3"exhaust
chevylovinfordtech is offline   Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Reply


Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Chevy and GMC Duramax Diesel 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:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools
Display Modes

Posting Rules
You may post new threads
You may 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



All times are GMT -7. The time now is 02:40 PM.



Powered by vBulletin® Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Friendly URLs by vBSEO 3.6.1