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Chevy Silverado and GMC Sierra Duramax Fuel Mileage

621 messages,  Last post on May 30, 2013 at 3:47 PM

You are in the Chevrolet Silverado & GMC Sierra Forum.

What is this discussion about? Chevrolet Silverado 2500HD, Chevrolet Silverado 3500, GMC Sierra 2500HD, GMC Sierra 3500, Diesel, Fuel Efficiency (MPG), Truck

Messages Page 3 of 63

#13 of 621 by quadrunner501

Sep 25, 2004 (11:56 am)

Or, if you see something that looks like injectors on the outside of the valve cover, because the LB7 design has the injectors UNDERNEATH the valve covers, so you can see only the fuel rails.

#14 of 621 Re: [quadrunner501] by blackmax

Oct 02, 2004 (6:48 pm)

Replying to: quadrunner501 (Sep 25, 2004 11:56 am)
Found an easy way to tell if you have the LB7 or the LLY that came out in mid 2004. The owners manual shows oil filler caps for each engine. The oil filler cap for the LB7 has the following: (Engine Oil, 15W-40W.) The oil filler cap for the LLY has the following: (Engine Oil, HUILE-MOTEUR.) When I raised the hood I saw that mine was the LLY. I understand that these engines do not get the fuel economy that the old style gets. Also, I ran a tank of fuel through with the tonneau cover rolled up and went from 15.8 to 16.8. I am now runing another tank through with the cover in place. I'll see if that really makes a difference.

#15 of 621 With tonneau cover in place.......... by ezshift5

Oct 11, 2004 (3:06 pm)

blackMax, how about that fuel usage?

#16 of 621 by blackmax

Oct 15, 2004 (10:54 am)

Fuel mileage dropped back to 16.0 with the cover on. BUT! I also found out that my tires only had 40psi in the front and 70 psi in the back. I have gauged them up to recommended 80psi and I am running another tank through. Will let you know.

#17 of 621 Re: [blackmax] by younger

Oct 20, 2004 (1:32 pm)

Replying to: blackmax (Oct 15, 2004 10:54 am)
2004 Crew short bed. I have been getting anywhere from 17-19.....current odometer: 2500 miles. Not too bad with a topper on the back. I'm guessing the mileage will get a little better once the miles start to season the engine.

#18 of 621 by 2manytoys

Nov 21, 2004 (8:50 am)

Though I have now sworn off Duramax trucks, I have owned two of them, an '01 and an '03. I never got any better than about 15mpg average with either one. If you drive them no faster than 65 mph you can do better. I was making trips out west where 80+ mph highway cruising speed is the norm. There the D-max returned about 13-14mpg empty.
 
I have three Cummins powered Dodges, two '03s and now an '05. the '03s will cruise at 80--90 and knock down 20 mpg empty. They are also quieter and don't have an impending injector failure in their future.

#19 of 621 Duramax gas Mileage by tahoelocal

Dec 16, 2004 (10:17 pm)

3 weeks ago, I just bought a 2005 Crew Cab Short Bed Duramax Diesel.. First off, I love this truck. I traded in my 2001 1500 ext cab. Need the diesel to tow my horses and the crew cab to put the kids in, needed more room..
 
I have been on a few long trips, I just got back for a long trip 400 miles round trip some highway and some city driving the last part of the trip was all up hill going from sea level to 7,000 feet. I got around 20-21 miles per gallon average speed around 80 to 65 some traffic with stop and go. Very happy with the mileage I got. Much better than my 1500, which I got around 19 or less on highway, and forget about climbing up the hills it was a dog, and towing it did good sense I was maxing out the weight limit.. Glad GM made changed this model year... Love my new truck

#20 of 621 Diesel truck advice for girls! by chani

Jan 16, 2005 (9:34 am)

I'm looking at buying my first diesel truck purchase to haul primarily, a 3 horse trailer, and for standard road commuting, not heavy hauling. We started out looking at F250's, but are also looking at the Chevy's since we don't pull really heavy loads, the incentives are attractive, and the cab has a better feel for me, since I'm pretty small; and the rig and bed are lower to the ground.
 I have some concern over the engine reliability,however. Any comments out there on the new Duramax engines?
 My biggest concerns, of course are engine and transmission reliability-- I don't want to get stuck out on the road with horses.
  Next is handling and safety; I'm not an experienced "big truck" driver. Turning radius is a factor, and the new tow package on the F 250's is an attractive feature.

#21 of 621 LB7/LLY by rooster9

Jan 25, 2005 (2:02 am)

The easiest way I found to find out if you have the older LB7 engine or the newer generation LLY engine is by looking at the vin number. If you have a Duramax diesel, the 8th number in the vin will either be a 1 or a 2. 1 is LB7, 2 is LLY. rooster

#22 of 621 Re: Diesel truck advice for girls! [chani] by tahoelocal

Feb 02, 2005 (10:50 pm)

Replying to: chani (Jan 16, 2005 9:34 am)
Chani,
 
I am a woman who just bought an 05 duramax diesel crew cab. Two words LOVE IT!!!!
 
I bought it end of Nov, I have almost 4 thoudand miles on it. I use it mostly on the highway, and I am getting 21 MPG. The engine rocks, I drive up in the Mountains at around 7 thousand feet, and their is no difference in power from there to sea level, it goes up hill, staying at 70mph with no problem. Plus all the looks you get from the guys is nice also..
 
I also haul horses, and will be using my truck to haul my two horse slant steel tow behind. I will also be hauling my friends 3 horse gooseneck. She has an F350 and my truck by far handles better, engine is better and I can haul as much as her.
 
From what I have been told this years diesel engine has been upgraded and is suppose to be better. The Allison Transmission is the best, never have to down shit. I live in snow country the 4x4 is excellent, had to use 4 low once and I was able to go threw 10 feet of snow with no issue.
 
If I where you, spend the little extra for the chevy, well worth it. Plus I also heard Ford has changed the diesel engine and everyone who has it is not happy, the engine has majot problems.
 
Good luck.

Messages Page 3 of 63

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