Duramax mileage??

[balthazar]

I am considering 'jumping the fence' from the Blue Oval Ranch to the BowTie Ranch. This would be a first for me after 4 Ford trucks.

Am looking at a '05 Silverado 2500HD Crew Cab 4x4 with the DuraMax/Allison. The truck is a great vehicle in ride, handling, braking and OMG would I wrack up tickets- it's quick.

The guy is only asking wholesale on it, which amounts to $26K.

I am wondering 2 things:

What is the standard powertrain warranty on the DuraMax? I've heard the extended is 7/200.

What are people getting for MPG out of these 'around town'? I get 16 out of my current truck and am fine with that, but some claim the DM is good for closer to 20 in the same circumstances. I just don't want to be lower than where I am now.

Any other opinions on the current Silverados???

[scharmer05]

i know a guy that has a 2006 GMC sierra with that duramax and 6sp allison. 2500, crew cab, long box. He put like a 500 chip in it and gets 20-22 highway.

[balthazar]

Is that a 500-HP chip or a $500 chip? Geared to towards power or economy?

[balthazar]

Found this online (to answer part of my own question):

The 2001 or newer Duramax equipped trucks have a 5-year or 100,000 mile engine warranty, while the powertrain is only covered for the first 3-years or 36,000 miles. However, GM has extended the Duramax fuel injector warranty for the 2001/2002 models to 7-years or 200,000 miles.

[bobo]

My next-door neighbor has a '04 Silverado 2500HD with the DuraMax that he uses for towing. I don't recall what fuel economy he gets, but he put a new chip in it, and it gets better mileage and performance.

[scharmer05]

$500 chip....i don't know exactly how the chip works, but it gets great highway gas mileage and puts out a little more than 400 horse. In 6th it is damn near idling as you go down the road, I'm sure that that is how it achieves that kind of mileage with that big of a pickup. I donno how well it would work if you only had the 5 speed allison/

[balthazar]

Well, I am going to answer all my own questions it seems.

Code LLY DuraMax (MY 2004.5 and later) is returning 15-18 locally, the bulk in the 15-16 range.

Code LB7 Duramax (2004.5 and older) is returning 17-18 as the bulk, with the 2nd tier falling into the 15-16 range and the 3rd tier in the 19-20 range.

Other source claimed 17-21 empty and 9-13 towing.

I have to really think this thru today, as the seller is going to pressure me for a decision tomorrow; he's foaming to get a '07 Tahoe. I'm not crazy about the price in general- that's an awful lot of 'green quarters'.

[Camino LS6]

Well, I am going to answer all my own questions it seems.

Code LLY DuraMax (MY 2004.5 and later) is returning 15-18 locally, the bulk in the 15-16 range.

Code LB7 Duramax (2004.5 and older) is returning 17-18 as the bulk, with the 2nd tier falling into the 15-16 range and the 3rd tier in the 19-20 range.

Other source claimed 17-21 empty and 9-13 towing.

I have to really think this thru today, as the seller is going to pressure me for a decision tomorrow; he's foaming to get a '07 Tahoe. I'm not crazy about the price in general- that's an awful lot of 'green quarters'.

Sorry, just found this post (been offline a few days). I'd confirm the 15-18 mpg numbers as about right. I love my '05 Duramax/Allison and highly endorse it. I dirve and work the truck hard and always stay above 10 mpg even when towing/hauling. Plowing drops it down a bit lower maybe and I have a very heavy foot most of the time. If driven conservatively, I would not be surprised to see much higher numbers. Haven't really done a long highway trip in the 20,000 miles I've put on it so far - low 20's wouldn't surprise me.

[Cray_Z28]

I have an 05 CC SB 4x4 LS with 51500 miles on it. Before I lifted it, I was seeing around 20 mpg average and about 16-18 mpg in town. I didn't see any good milage (above 13) until about 20k miles on it once it started loosening up. Mine has a 6" lift kit on it with 315/70/17 tires on it. Milage dropped to 13-15 average. Installed a 4" down pipe back exhaust unit on there and milage increased once the cat was removed and the stock muffler replaced. Now I am seeing 16-18 mpg average. I think that I could have got near 25 mpg with the 245 stock tires and stock suspension, but it is only a theory. All these numbers are with summer fuel too. It takes a hit with winter blend. I have the DiabloSport Predator tuner with the 40 hp tune. With performance enhancers like that, it throws the DIC off so it reads 25 mpg, when hand calculations shows other wise. My EGR valve has also been defeated which helps reduce EGTs. www.dieselplace.com is a good source for information. The ride on the truck is excellent. 26K is a great price too!

[balthazar]

Well, I bought this truck yesterday.

'04 2500HD LT CC/SB Duramax 4x4, 46K miles, interior is in excellent shape, exterior has some scratches & I have to re-align the front bumper (should be no prob). Something is up with the steering- there's an occasional minor grating that you feel more than hear- gonna have that checked out. Otherwise it's a very nice truck, a real monster. Paid $24250.

That's a lot of $ for me to spend on a vehicle, more by far then I ever have, but at that price I should be able to drive it for a year or more and sell it for what I paid for it, should I choose to.

[Cray_Z28]

The intermediate steering shaft can make you think something is loose in the steering. The only "fix" GM has to offer for it is to remove it, lube it, and reinstall it, to have it reoccure 15000 some miles later.