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Chevy Silverado and GMC Sierra Duramax Fuel Mileage
I just bought a new 2004 Duramax Chevy, extended cab with short box. I filled the tank at 226 miles and showed 17.2 mpg. I filled again at 500 miles and now show 15.2 mpg. This is kinda discouraging. Is this normal? I bought the D/MAX expecting 18-20 mpg. The only difference is a tonneau cover being added between fill-ups. I drive 25 miles to work on four lane highway at approx. 70mph. Any comments??
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But...manual transmission (6 spd), and lightweight regular cab.
And the new LLY is a completely new design, new heads, new injectors, new garrett turbocharger.
Is that the new GM DuraMax? Is it a 2005 model engine? How is the power compared to the older models?
The hp and torque increase is for Allison 5 speed automatic equipped models only, not the ZF-6spd manual.
The hp and torque of the previous LB7 was 300 hp, 520 lb/ft torque.
Unfortunately, that's exactly what's been happening. GM recently sent out notices to owners of 2001-2002 Duramax diesels that they *may* experience injector failure caused by high fuel return rates or cracked injector bodies, and that accordingly, GM will extend the warranty on *covered* failures (not all) to 7 yrs/200,000 miles. While that's a small positive step, my $0.02 is that GM has not gone far enough. Since they KNOW they have a problem with the Bosch injectors, the appropriate and ethical course of action would be to issue a recall for all affected vehicles, and replace the bad injectors with the updated ones the owners should have expected in the first place. FYI, these injectors operate under very high pressures, up to 30,000 psi, making them completely different animals than cheap injectors in gasoline engines which operate at a lowly 50 psi, and cost less than $100 each. The bosch diesel injectors cost upwards of $500 each, 8-12 hours labor to replace them, and some have been replaced 8 at a time under the GM warranty. You do the math...that's quite a bit of exposure for an owner to accept. Diesels are fun, but you could pay to play if you hold on to one beyond the warranty period. The bosch injectors are on national backorder at this time. Dealers cannot give a time frame if you are unfortunate enough to suffer this malady, except first come-first serve.
The other features behind the new heads and variable inlet garrett turbo-charger are primarily to address emission concerns and future low sulfur diesel fuels.
The cetane rating of fuel affects mileage and power, but it's hard get reliable information, or even know what you are getting at the pump. Find a reputable fuel source that you trust, and stick with it.
I think your mileage will get better, however if you have the newer LLY design, some reports are that it hasn't been getting as good a fuel mileage. It makes more horsepower, so the re-programming that matters most is possibly located underneath your right foot.
The old design is the LB7, new design is LLY, a mid-year 2004 introduction. The LLY has more horsepower and torque too, and apparently worse fuel mileage...but again, that could be a consequence of the driver.
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.
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
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.
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 [non-permissible content removed]. 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.
2001 2500HD, D-max, Allison, Crew Cab, Long Bed, 3.73, K&N air filter, fresh oil change, 82,000 miles:
From Cincinnati to NYC (eastbound), I averaged about 20.5 mpg unloaded, driving 75-80mph.
From NYC to Cincinnati (westbound), I averaged about 18 mpg, with about a 2000lb load that stuck above the cab (extra windload) and a completely packed cab, driving 70-75mph.
I've had no significant problems to date w/ my D-max. I'm concerned about the injector issues but I would think that you would see signs of the problem in your oil if they are leaking within the cylinder heads.
Also, as a note, fuel mileage is directly proportional to the drivers ability to drive smoothly. When my girlfriend took a turn driving, our mileage dropped about 2mpg because she brakes more often and resultantly accelerates more. I usually let the truck coast down to stops by anticipating them and keeping good distance between me and the next vehicle.
As an fyi, installing the K&N air filter had no appreciable impact to perceived performance or economy.
MPG ganges in the 17's. I cruise 80-85 to work daily (74-mile round trip). High 17's. I had a 1,200-pound load for over a tankful for those commutes. 17.3.
My old gas truck had to drop to second to pull a local hill with my race car and trailer. The Duramax? It was in 4th gear before I realized what was going on - that I was almost at the top of the hill with little effort. I looked back to make sure the trailer was still there! I didn't have it in tow mode either. 16.8 MPG with the race car back there.
Can't argue with the torque. Amazing truck.
24,000 miles on it now. I'm talking to Banks now - we're going to give it a boost!
2004 Duramax Silverado Crew Cab
Just as a matter of info, typing in all capital letters on tthe internet is difficult to read and in most circles is considered shouting. When posting, can you turn off your CapsLock? Thanks!
kcram - Pickups Host
My mileage has dropped, have I gone to far?
mpg so far and pretty pleased with that.