Mileage comparison to other Manufactures?

[rsparks]

I know I am going to use a dirty word here but any one know how the mileage of the Duramax compares to other rigs such as the new 6.0 L Ford Power Stroke? Just kind of wonderin.

[VA_Dmax]

Our business uses both a 2003 LB7 Duramax and a 2004 6.0L Power Stroke. My Duramax is a 6 speed and a short bed ext cab and I average overall 18 mpg. My partner's 6.0L is a F350 srw automatic ext cab long bed, and he is lucky to see 15 or 16. Usually he is around 12 or 13.

[Bill Voitel]

Best so far with the replacement for the burb has been 19.4 flat land with cruse set at 65 at 70 will drop right to 18.0 with my neighbors boat approx 4K
at 55 on the two lane 17.2 It has a 3.73 diff gear.
another tip from the dark side :eek: :eek: :eek:

[Jim Brzozowski]

Went hunting to Colorado, My Duramax,bed fully loaded to the roof of the cab, and pulling a tail dragger travel trailer. The other guys 6.0 bed only sligltly loaded and pulling a short GN travel trailer. We traveled together, stopped at the same station and on each fill up his held 9 gallons more than mine every time. Both were stock. In all fairness to him, he only had 1400 miles on it when we left on the trip. I'm sure it would do better now, but not that much better!

[More Power]

Here's a quote from the 9/04 issue of Motor Trend, where they compared a new Dodge/Ford/GMC diesel pickup in a comprehensive series of performance, towing and fuel economy tests.


"The GMC grabbed best-in-class mileage with an 18.6-mpg figure, followed by the Dodge (17.4) and the Ford (16.6). That's a significant seven and 12 percent advantage, respectively."MP

[rsparks]

Thanks for the info to all who replied. More Power do you know if the GMC in the test was an LLY or LB7?

[More Power]

It was an '04 LLY with 590 lb-ft of torque.

MP

[royalglen]

It is interesting that the common view of Mileage (MPG) is that an engine will get better mileage after it`s "broke-in".Are these engines not so percise that the tolerances won`t change much.If there is a "break-in" period-what are we "breaking-in".The differentials maybe but this should`nt effect MPG. I may be missing something so please advise what engineering principle i`m missing.My 02 and 03 gave me the same mileage the day i bought them as the day they went "down the road". I might add they were both very good on fuel pulling 34` 5th wheel.

[More Power]

Every moving part in the engine and drivetrain contribute some amount of drag or friction, and subsequently, the power required to move the vehicle. From piston rings in freshly honed cylinders, all the way to the wheel bearings, there are a lot of individual moving parts that move more freely with additional time and miles..... I saw a tank in the 15's during the first couple. It's not ever been there since (when running unloaded).

A good analogy would be compare all synthetic oil and lube to petroleum products in the same truck on a dyno.

MP

[tanker]

Well with less than 2000 miles on mine, I got 19.4mpg that was on a 300 mile interstate run, the computer said 19.8mpg, so when I filled up and did my own caculations I got 19.4. That was running at 70-73mph. On a previous trip the computer gave me 20.4mpg at 65-68mph. but never did a caculation after a fill up. I very pleased with the new D-Max as my ole 95 6.5 only got about 16-17 mpg at those speeds. In town driving lots of lights etc, short runs, back and forth to work, I'm seeing 15+mpg.
Plus it seems to run strong. ;)

[Jim Brzozowski]

royalglen, if you started out towing right away, you probably seated the rings pretty quick and didn't notice an improvment in mileage. The differential is set up very tight at the factory, thus the heat build up until its broken in, the transmission gears also need to be run in before it runs cooler, but I think the biggie is the ring seat. The better the ring seat, the more efficent use of the fuel injected. That is what I found on mine. I didn't tow until I had almost 10,000 miles on it and the first time after I towed I could hear the difference and feel the difference. I know that is when the rings in mine finally seated. Gas Engines nowdays come with moly coated rings which will seat in about 30 minutes. I've put engines together, made two easy passes down the strip and then raced it. I don't think diesels use moly rings. Steel and especially those with chromium in them are much harder and take longer to run in.