I have a 01 Duramax Diesel. Im thinking about getting a new 09 Deisel. I wanted to know what kind of fuel mileage everyone is getting espcially with the new cats. Is it worth it or is the big gas motor better? Any help would be great. Thanks

You cannot get the big gas engine from GM-- they do not put it in new 3/4 trucks. 6.0 engines will get 12-14 . Diesels will get 15-20 depending on your driving style. :cool:

15 city 18 hwy, most report worse but that's my hand calc average first 17K.

Worth it finacially? No.

But worth it in so many other ways....In fact it's.... ** PRICELESS **

RIP 8.1 Killed before it's time. Was a great motor for thee trucks. I get about the same mpg as my LLY for what it's worth.

I think the needs vs the wants should be closely calculated.
Including the the above noted "Priceless" factors.:cool:
I noted that you have a dually in the avatar, If that is what you have and you use its abilities frequently, then yes another DMax truck would be what I would get over the gas truck.
I have the 2500 crew long bed 08 get about 15.7 mpg or better in mixed driving empty it is my daily driver my truck is stock mechanically and I do not do any crazy fast driving but I run 70 on the highways. If I was given a choice I would get the same truck again.
I hope this has helped and the 09's have few new toys that the 08's do not have but other than a few new toys the 7.5 - 09 are pretty much the same trucks, I'm glad I got one, just wish I had waited 6 mo for the current better deals vs what I paid.

Empty, I average just over 17 mpg (dropped to just over 16 with winter blend). This is mostly 2 lane country roads, hand calc. Even if the price of diesel gets on par with RUG, I have doubts the diesel will pay for itself.

I'll be putting ~2500lb of camper and gear in the bed and traveling with this truck. I wanted to be able to climb the western mountains, and the eastern ones for that matter, without the downshifting a gasser would need to do and wondering if a piston is going to come through the hood. That's why I spent the extra money. The higher mpg is just an added benefit.

Diesel or gasser? All depends on what you want to do with the truck...

does anyone now when they stopped making the 8.1 gas motor cause Im not sure if the new 6.0 gas motor has enough stem so was the 8.1 a good powerful motor?

does anyone now when they stopped making the 8.1 gas motor cause Im not sure if the new 6.0 gas motor has enough stem so was the 8.1 a good powerful motor?

They quit offering it when the old body style went out; 2007. Yes it was a geat motor. Would ass everything on the road but a gas station! You can still get it in the Medium Duty trucks.

I had an 03' 8.1 in the 6spd manual and loved it, my new LMM does have alot more power but not alot better on mpg's yet( I only have 8,000 miles), hopefully it wil get better. As posted above the 8.1 wen't out with the old body style. My dad has an 08' 6.0 and his has never been over 9.0 mpg's according to his DIC (never hand calculated) but he only has around 2500 miles on it. Hope that helped a little.

I know my truck is new with less than 3K on it but all I have been getting is 10-11/14-15 MPG's empty. I was really hoping for better and I hope I don't have to drive another 47K before I see any improvement :o:.

I know my truck is new with less than 3K on it but all I have been getting is 10-11/14-15 MPG's empty. I was really hoping for better and I hope I don't have to drive another 47K before I see any improvement :o:.

I get close to that as well but I have a DRW utility bed with all kinds of crap on the top of the box .... and yes this is all hand calc.

2 questions: 1 for RINGNEKS-does your dads 6.0 have enough power to tow a 28' trailer loaded with a car and parts? also is that bad gas milage normal for the truck? thanks
2 forAahhyes68-do you have the 6.0 gas motor? how do you feel about the power? thanks

RR, I just updated my sig but I have the D/A combo.

MaxMike, Yep it's pretty much empty and a SRW. I do carry 500#'s of sand right now for the Winter. The mileage plain sucks, it's worse than I ever thought it would be. Oh well.

Aa-if you could do it again would u go with the gas 6.0 or buy an old truck with the diesel without cats or the 8.1 gas motor?

Imo I would wait for the 2010. The scr sounds like a better way to deal with nox gasses. I love my lmm but the mpg isn't great. I just went to Florida and back towing my 12000 lb 5ther. 3450 miles round trip (2920 miles with trl) and my average for the whole trip was 10.3.... I could have done a little better but when I pointed the unit home the avg speed was 65 and 75 for the last 200 miles.

Aa-if you could do it again would u go with the gas 6.0 or buy an old truck with the diesel without cats or the 8.1 gas motor?

I would buy a 2-3 year old LBZ/LLY with 40-50K on it in good shape, no more gassers for me when it comes to towing. I was stuck, I had an '06 1500 Suburban and couldn't sell it and needed the moola to move on. I got 18K on a trade-in with a 21,861.55 balance including taxes OTD.

At the time, locally there was a '06, 3500 Dually/CC/D/A/power/cloth w/23K on it for sale by owner for 26 grand !!

THAT's the truck I should have bought looking back. Just about out of warranty, and could tune it easily for econo/tow without looking back.

There are deals out there if you have some good ca$h. I was searching in all 48 states and there were some deals that I could have flown in, drove home and still saved thousands.

ok I guess I should look for a used truck rather than a new truck.....

ok I guess I should look for a used truck rather than a new truck.....

Don't just take my opinion brother, I'm just sayin' that I personally would have been better off with a 3 year old used truck. But again, I was stuck with the Suburban sooooo.... Here I am.


Give me a little time and I'll post some post-sales of the Dealers Manheim auction sites here in SE MI. This is where the dealers get there used trucks and cars, there's usually a handful of various diesels that go through weekly. My buddies is a car-jockey and gave me his password to th Manheim's website ):h. When you know what dealers are paying, it's easier to negotiate.

Steve

2 questions: 1 for RINGNEKS-does your dads 6.0 have enough power to tow a 28' trailer loaded with a car and parts? also is that bad gas milage normal for the truck? thanks
2 forAahhyes68-do you have the 6.0 gas motor? how do you feel about the power? thanks

My dad's 05' 6.0 was not getting much better, I remember telling him he should have got the 8.1 because there was no difference in fuel economy(remeber mine was a manual 6 spd), I never towed with a 6.0 or driven in one while towing but my dad said his 05' he towed a buddy's 26' toyhauler loaded with gear for four guy's and 100 gallons of water( no bikes) with ease from oregon to Idaho on several occassions. I think the new 6.0's have more power in 08.

I picked up my 08 in September and only have 900 miles on it so far since it’s parked for the winter. I can tell that the mileage is considerably lower on the 08 LLM than my 05 LLY. Granted, its not broke in yet and the tires are taller but my mileage to date (DIC) has been 10 – 11 MPG.

Imo I would wait for the 2010. The scr sounds like a better way to deal with nox gasses. I love my lmm but the mpg isn't great. I just went to Florida and back towing my 12000 lb 5ther. 3450 miles round trip (2920 miles with trl) and my average for the whole trip was 10.3.... I could have done a little better but when I pointed the unit home the avg speed was 65 and 75 for the last 200 miles.


i just did a similar drive with a 28ft enclosed prob weighing in at 11k. went from nashville tn to orlando fl around town for the week and then home around 1300 miles averaged 10.5 with a dirty air filter and a fuel filter with 10k on it. i was really hoping for at least 12-13 but iwth a clean filter and new fuel filter it prob would have got it.

is the 6.0 gas motor in the older trucks the same as the new 6.0 motor? Just trying to figure out what direction I'm going to go in. Thanks

is the 6.0 gas motor in the older trucks the same as the new 6.0 motor? Just trying to figure out what direction I'm going to go in. Thanks



Current 6.0L is rated at 360HP and 380ft lb of torque.
http://www.gmc.com/sierra/2500HD/specsEngine.jsp (http://www.gmc.com/sierra/2500HD/specsEngine.jsp)


The 1500 GMC even offers a 6.2L rated at 403HP and 417ft lb of torque. (Higher HP rating than the Duramax!)
http://www.gmc.com/sierra/1500/specsEngine.jsp (http://www.gmc.com/sierra/1500/specsEngine.jsp)

i just did a similar drive with a 28ft enclosed prob weighing in at 11k. went from nashville tn to orlando fl around town for the week and then home around 1300 miles averaged 10.5 with a dirty air filter and a fuel filter with 10k on it. i was really hoping for at least 12-13 but iwth a clean filter and new fuel filter it prob would have got it.

I was kinda hopin for 12 mpg myself. I started off nice and easy on way down and as I got further south I noticed an improvement in fuel.(not winterized) the mpg started going up. It did get as high as 11.5 but then my foot started to get real heavy.

We were down at North Port fl at the Ramblers rest campground. can't say enough good about the place. We had an awesome time and met some really nice people. planning for next year again. See attached pic. they kept on telling us to watch out for gator in pond....:D

The dirty air filter ..... In my western star I notice a decrease in mpg right after a change of the air filters.(small but noticeable) The fuel filter (I have a davco Glass filter that you can see) this helps you know where you are buying water instead of fuel...but unless that sucker is 3/4 full it does not affect mpg. Mind you its a lot lager than the fuel filter on on dmax.

I just bought 08 2500 6.6 diesel and am only getting 10-11/14-15 also. Fast like a rocketship though.

is the 6.0 gas motor in the older trucks the same as the new 6.0 motor? Just trying to figure out what direction I'm going to go in. Thanks

is the 6.0 gas motor in the older trucks the same as the new 6.0 motor? Just trying to figure out what direction I'm going to go in. Thanks

Basically the same motor, just higher output.

I'd keep the old diesel(01-04.5) they get the best mpg out if them all. hum emissions maybe!!

I'd keep the old diesel(01-04.5) they get the best mpg out if them all. hum emissions maybe!!

Depends who you talk to. They also had the most problems and lowest horsepower and torque.

Just with injectors, ya they aren't cheap I know! A chip takes care of all the lak of power, puts them easaly past the rest

I average about 14MPG with my 2008 dually, and that's with the larger tires listed below. I get about 6 to 7MPG towing my toy hauler.....