worst milage in the world!

[catoiler]

And I ain't buying the "put more miles on it it will get better" bs the dealer keeps telling me(along with others)this is the 6th one and not one has picked up more than 1-2 mpg better,I don't call that a improvement. meanwhile the price of the trucks goes up along with the fuel!!

 

[JAKE 2544]

I feel your pain,i traded a beautiful 05 with kore suspension and a ton of accessories on a custom ordered 6. 7l. drove it for 3000 mi and had the dealer buy it back in trade on a left over 07/5. 9l. Cant tell you how releived i am now that i'm back in a 5. 9. There are still plenty of left overs out there,good luck. The lots will soon be flooded with 6. 7L. from unhappy customers.

 

[JCleary]

I feel your pain,i traded a beautiful 05 with kore suspension and a ton of accessories on a custom ordered 6. 7l. drove it for 3000 mi and had the dealer buy it back in trade on a left over 07/5. 9l. Cant tell you how releived i am now that i'm back in a 5. 9. There are still plenty of left overs out there,good luck. The lots will soon be flooded with 6. 7L. from unhappy customers.

I guess it's time to update your sig...

 

[RGrizzle]

i have 5200 miles on mine and am pleased with my fuel mileage for the horsepower . off the lot hand calculated i got 17. 7 mpg on 2 lane roads . since then . it has gone up to 18. 6 (empty) . i checked it bout a month ago , and pulling my 12,000 lb fifth wheel across the appalachians , i averaged 12. 6 mpg . i just got back from a trip to the smokey mountains with the fifth wheel and i pulled through the smokey mountain national park which is a lot of steep and long pulls and still got 10 mpg with it on the 185 mile trip. i love my truck. Oo.

 

[KEpperly]

I want your truck RGrizzle. Mine gets 12. 5 mpg towing a 5,000 pound trailer car combo the best I've ever seen was 15. 5 and that was when I picked it up from the dealer. right now its been in regean for the past couple days its getting just over 11 mpg empty. I also drive like I have an egg under my pedal. as I did In my 5. 9 just had alot better results in the 5. 9. I agree that this is the best stock truck Ive ever towed in

 

[Sasquatch]

I have around 15,000 on my 07. 5, and I'm getting around 14. 5 around town (winter fuel) in small-town (Basalt) Colorado.



If I baby it on the highway, I can get mid-17s pretty easily, and mid-18s (driving 55 mph) during the summer months.



I have a heavy dually, with lots of add-ons, so the 2500 guys should be doing as well or better.



If you're getting terrible (9-10 mpg) mileage, I've gotta believe there's a problem that can be remedied.

 

[RGrizzle]

I want your truck RGrizzle. Mine gets 12. 5 mpg towing a 5,000 pound trailer car combo the best I've ever seen was 15. 5 and that was when I picked it up from the dealer. right now its been in regean for the past couple days its getting just over 11 mpg empty. I also drive like I have an egg under my pedal. as I did In my 5. 9 just had alot better results in the 5. 9. I agree that this is the best stock truck Ive ever towed in

i noticed on your signature that you had an auto with 4:10's . this would account for some of the difference as mine has the manual with 3:73's .

 

[Turbo_Bob]

One thing everybody is forgetting about, Ultra Low Sulfer Diesel Fuel, that kills MPG. I lost 1 MPG using Low Sulfer Diesel Fuel compaired to the regular diesel fuel.

The other thing is the diesel injection into the exhaust stream, to clean out the grid, that wastes fuel right there.



But, I test drove my nephews new 08 3500 with the six speed automatic, 3. 73's and built in exhaust brake, all I can say is WOW ! If I could afford a new truck I would sure buy one, even if it gets only 18 tops.

 

[jimnance]

Agree with ya Bob. DC got it right when they paired the 6. 7 with the 68RE. It is a sweet combination.



I haven't had any problems... yet. Mileage could be a bit better, but considering the EGR and DPF with fuel wasted doing regen I don't think 15-16 MPG is all that bad.



I'm waiting for someone to figure out how to defeat some of this stuff and regain the lost mileage.



I still have my '05 with Edge Attitude. On level 2 towing my fiver, my stock 6. 7 will run right along side under the same conditions. The extra two gears really make the difference when towing.

 

[catoiler]

But, I test drove my nephews new 08 3500 with the six speed automatic, 3. 73's and built in exhaust brake, all I can say is WOW ! If I could afford a new truck I would sure buy one, even if it gets only 18 tops.

Yep if I could get 15-16 I would be happy but 10mpg around town sucks!! But she is a towing beast!!

 

[Tom Schuster]

It seems my truck gets better mpg at 75 to 80 rather than 65 to 70. Any one else notice this trend?

Well, mine certainly gets better mileage at 70 mph than it does at 55 mph, which is contrary to what I keep hearing--that you can save fuel by driving 55 mph. Mine gets upwards of 18-19 when I drive between here and Missoula (when I can put it on cruise at 70 mph) and a steady 15-16 when I am driving around here at home (half highway, half town driving). It got better mileage before the snow tires went on but that always happens. It's got about 8500 miles on it.



My previous truck ('99 2500) always got between 18-22 mpg and that was hard to give up, but my new truck does better than I thought it would. And it's so much more fun to drive!



Janet (the wife)

2007. 5 3500 MegaCab

 

[gsbrockman]

I still have my '05 with Edge Attitude. On level 2 towing my fiver, my stock 6. 7 will run right along side under the same conditions. The extra two gears really make the difference when towing.

Excellent points... ... ... . I have heard similar comparisons from others elsewhere.



Lots of people say "there's only a 25 hp / 40 ft/lbs torque difference" over the 325/610 engines, but, in the grand scheme of things, the 68RFE sure does git-r-done a lot more efficiently. In addition, especially when backing up with a trailer, the 68RFE really shines.



Greg

 

[Sasquatch]

I know that this has been posted before (probably in this thread, in addition to my earlier reference), but "winter fuel" formulations make a BIG DIFFERENCE, so don't overlook that factor when mulling over diminishing performance since late fall...



Around here, they've been pumping winter fuel since Nov 1st, and there's no question but that it's cost me 1. 5-2. 00 mpg.



Also, and this is huge, all engines are more efficient when they've come up to optimum operating temperature, their fluids and lubes are at normal viscosity, etc. Lots of the problems we're experiencing now (fuel mileage) are related to guys taking short hops in very cold weather. A run to the market, post office, or whatever -- trips that take ten minutes and span 5 miles, each way, are fuel milage killers of the worst sort. It doesn't matter how carefully you drive (egg under foot, etc. ), you're going to get gawd-awful fuel efficiencies, if you're driving that way.



I take my old lady's car (whenever possible) on weekends, at nights, and/or any other time I can, when the transportation need falls into the "errand" category. Our trucks will eat us alive if we use these "Clydesdales" to fetch the mail.



I've seldom gotten less than 15 mpg (hand calc'd) but I make an effort to let the truck warm up for 5-10 mins. in the driveway (with high-idle enabled), and I've found that the best mileage returns, for this truck, happen when I'm holding it on 60-62 (not 55). My rig feels like it's lugging the engine a little bit at 55 in D. In overdrive, at 55 mph, it's a little around 1475 rpm, and it feels lazy and sluggish making small hills. At 62, the tach is at around 1550, and the truck is more responsive and in a better part of it's power zone.



This sounds counter-intuitive, too, I know, but I live about 4 miles (almost straight up) above the Roaring Fork Valley, and, when I turn off Hwy 82 on the valley floor, and head up Basalt Mountain to our home, I push the truck hard going up the hill. This is about a 4 mile climb and an elevation gain (to our driveway) of about 1200 feet. I'm convinced (whether it's true or not, who knows?) that this daily workout helps keep the DPF happy, and the truck running clean.



I hope you guys get your problem trucks figured out, because it's a shame to have spent so much money on a piece of engineering, and then be bitterly disappointed by it.



I honestly think that "Brands F, and GM" are having similar problems, and that people who tell you otherwise, aren't being truthful. My brother lives in Eugene Oregon, and has a brand new Duramax, which he's fitted with lots of aftermarket stuff, including 35" tires, a seven inch lift, and a Road Armor bumper. He's going to add a WARN 16,000, as well, and he loves his truck, but he's miserable about the mileage (town 11-12, hwy 14-15)



We're all in the same boat, but some common sense and a patient approach can help lessing the fuel-mileage pain.



I do believe, sincerely, that there will be an after-market "fix" for achieving greater efficiencies, and I don't believe that they will necessarily involve gutting our factory emissions system.