About Newer Diesels

[SteveH]

Originally Posted by lsmith

19 mpg - 21 mpg on highway empty

average 14 mpg with 28'

should have bought a Dodge

I actually considered one, but couldn't stand the ride.

[slowmover]

Yup, the HP got too high to support great fuel mileage. 2WD and the man trans are the other key components. (As well as highway rib tires).

The driver makes the biggest difference afterwards. For big trucks, all else identical, the spread between drivers is 30% in fuel mileage. Changes in speed and use of the brake kill mpg. City traffic flow is 15 mph, nationwide. If one logs highway elapsed times, one learns that traveling below the limit increases the time of "steady state". In both instances one learns to never come to a stop, use the brakes or change lanes. And THAT changes all other habits.

Whatever the vehicle, one can improve on initial numbers. 10-mph under the limit on the highway/5-mph under in town is the place to start.

[barts]

Originally Posted by overlander63

Steve, pretty much all the '08 and newer diesels will have sucky mileage because of the particulate filter.

Our 2009 Jetta turbo diesel gets 40+ mpg on the freeway, and still does 0-60 in just under 8 seconds. It's subject to some pretty tough emission standards.

I think mileage on next gen trucks will improve as they get things sorted out. The current generation of trucks was designed for low fuel prices.

- Bart

[crispyboy]

We have a 97 VW Jetta Diesel. It has dropped about 3 mpg since ULSD fuel was introduced. I keep additives in the fuel tank but that only seems to help with the amount of smoke. I am down to 42 mpg in town, 46 on highway.
Recently I have had to gut the catalyst on this car. It finally plugged up after 175K. It took quite a bit of diagnosis to find the problem. With all the computer control and sensors these are not easy cars to work on.
From all of my reading it seems that all new diesel trucks are suffering from the same poor mileage trouble. It seems that the displacement had to increase to make up for the emissions equipment which robbed the engine of power which in turn would use more fuel.
STEVEH I think your right in the ballpark with the fuel mileage of your 08 Duramax. Newer trucks just are not as efficient.

[barts]

Originally Posted by crispyboy

Newer trucks just are not as efficient.

This is difficult to prove w/o a standardized test for fuel mileage. I suggest that it's high time the manufacturers provided mileage data for our trucks. That way you could weigh the advantages of that extra 75 ft-lbs of torque against the 2 mpg difference while towing, for example.

- Bart

[AirsDream]

Of course, we're currently running winter fuel, which has lower BTU content, but on my '09 GMC Duramax, I get pretty much regular 20-21 mpg running empty at 65-70 mph. on long trips. Worse in town, of course, trying to accelerate all that mass. Am currently a towing trip and first 750 miles averaged 13.4 towing at 65-70. I am not complaining. Like the torque and control!

[ESCAPE POD]

Originally Posted by StingrayL82

There's no doubt that a P-pumped 12v Cummins will get the best mileage; you'll also be killing Mother Nature, according to the nature kooks, but I'm pretty sure that Mother Nature will still be around and able to regenerate itself, long after we've gone the way of the dinosaur...my opinion, of course. Then again, if the Earth can survive massive meteor strikes and super volcanoes, I don't think that diesel soot is going to faze it one bit.

Not to hijack this thread, but I guess you don't like to fish, hunt or think too much about the millions of Americans with respiratory problems made worse by diesel particulates (just take a look at San Pedro, CA: much higher rates of lung ailments because of ship-generated diesel exhaust). Sure, the planet won't disappear, just the life it supports. I like the idea of cleaner diesel, and I'm not convinced that science and engineers have exhausted their ability to produce both powerful engines that also spew less poison. Like you said, just my opinion!

[StingrayL82]

Originally Posted by ESCAPE POD

Not to hijack this thread, but I guess you don't like to fish, hunt or think too much about the millions of Americans with respiratory problems made worse by diesel particulates (just take a look at San Pedro, CA: much higher rates of lung ailments because of ship-generated diesel exhaust). Sure, the planet won't disappear, just the life it supports. I like the idea of cleaner diesel, and I'm not convinced that science and engineers have exhausted their ability to produce both powerful engines that also spew less poison. Like you said, just my opinion!

Well, actually I do like to fish and hunt, and I have COPD, thanks to my father who smoked in the house and in the car, with the windows up, as well as all the crap I breathed in, when I was in Kosovo. Did I mention I'm only 36? Advair tastes like crap, by the way. What does that have to do with diesels and the mileage they get because of their emissions components?

[Catman6]

I started using Motorkote oil additive, and then started using the low sulfur additive in all ofmy rigs, as well as my Dodge Cummins. The oil additive made an improvement on how hot my trucks run, as well as cold starting [they crank easier]. The fuel additive is where I saw the biggest increase in usage. If you bulk order it, you can get it cheaper. I order 10 cases at a time and get a 20% discount w/ free shipping. I saw a solid .75 - 1MPG increase in my rigs. I use it every time I fuel up instead of every 3000 miles, and my Dodge has seen an improvement as well. I just pulled a 14,000 lb. dump trailer through Maryland up to eastern central PA and back, and averaged 11.7 MPG. Using htese additives will also increase the life of the fuel injectors and the fuel pump [for sh$ts & giggles try pricing one of the newer electronic ones - I had a heart attack when I got the bill!].

Oddly enough, one other thing I noticed made a difference in my rigs was switching over to Mobil Delvac oil. I don't understand why, but I picked up a little fuel mileage with this switch.

Other than this, driving habbits, slowing down, and taking in to account wind, there's not much you can do.

Good Luck!

[TerryC]

Hey Guys,

Buck Up, take a trip to London with all the diesel trucks, buses and taxis and diesel cars there and you'll appreciate the emission standards in the good ole USA!
I know it's tough to swallow the mileage you get with the new standards, it will get better. We keep getting more and more vehicles on the road contributing to more and more pollution. Got to think of future generations NOW!

TerryC

[slowmover]

You don't need London. Just walk through any truck stop on a hot day. It is the accurate definition of stifling. I added some HVAC air intake filters to my FREIGHTLINER and was suitably amazed at how much better it was.

Stingray . . you're too young to remember how bad it was to drive into Los Angeles in the 1960's, it was eyeburning. My folks moved away in the 1950's after a few years of residence, and some on my Dad's side moved away at that same time (after being there since the 1890's) as the air pollution was so bad.

Catalytic convertors worked out pretty well. Yes, I, too, am bummed that overall economy is down with present mandates. I'll live with it. It is my sincere hope that tailored algae can be designed to produce "diesel" that has what we need from it and nothing more.

Doctors and pill companies get waaay too much credit for American's life longevity, anyway. The majority was produced by the "socialism" of mandating sanitary sewers and clean drinking water; moving livestock/abattoirs out of cities. Or, the "socialism" of mass electrification.
The causes of ill health today are "probably" majority environmental. Pollution controls on new vehicles mean I'm not making a mess for someone else to clean up . . and denying the benefit gives corporations (and government; see Rocky Flats, etc) the philosophical argument that their "profit" should always come at the "expense" of society . . that would be more of the "trickle-down", ah, theory.

I cannot see being in favor of open waste streams, THAT should be closed from hereon. I need the service of a private vehicle . . but no one else need suffer from that choice (beyond what we, openly, decide as a society is acceptable risk).