I have just got my 05 4 dr. 4x4 it has currently got 1800 miles on it. Let me just say the truck is stocke except for the H2 wheels an 315/75/17 tires. I know what you are thinking well theres your problem there!!! An this may be part of the problem but I average 12.5 mpg @ 70 MPH which i will say is maybe 75 mpf allowinf for the larger tires. But witht he stock tires I only saw 13.3 as the highest... Will the mileage increase as the truck breaks in???? My sales man told me about a guy who was getting like 13 MPG an around 3800 miles it went to 18 mpg.. This seems kinda far fetched.... anyone had this situation where as the motor broke in it got better MPG ????? Thinks.. Im guessing an exhaust an intake an maybe a mild tune may help.. Maybe I guess..

with my 04.5 crewcab short box 4WD LLY the worst mileage I have seen is 13 stop and go 5 miles to work and back. I have 2K miles so far, best was >19 @70+ on a 200 mile highway trip up over the oregon coast range. One tank pulling a 5000 lb trailer and round town was 14+. Overall average for 2K miles is just over 14, with most of it to/from work round town.

with my 04.5 h2s juice on level 2 full 4" exhaust and disconnected egr i got a best of 17mpg mixed driving ie sitting through 3 lights at times then traveling 50-60 on rural country roads

before the mods (totally stock)the truck had a best of 18mpg in the same conditions

I live in the city, and drive to work in the city, all stop and go and get arond 15mpg. And that includes ALOT of Edge/Attitude juice level 5 hole shots from light to light. But I do have 16,000 miles on my truck now to.


I also had lowsy fuel mileage at first. Give it time, it'll get better.

Based on my truck and after reading lots and lots of mileage posts, I would expect a stock good running LLY truck to get about 19 mpg flat highway traveling 65 to 70 mph. I would expect about 15.5 city driving, no rush hour stop and go.

This is totally a subjective opinion on my part. There are a few LLY owners reporting better numbers than this and there are also some in the same range as you. I also noticed the Dodge and Ford owners also report a wide variation in mileage just like us.

There are many posts saying the mileage drops rapidly over approx. 70 mph or 2000 rpm. Your 75 mph speed (or more???) may be part of the reason for lower mileage compared to the other LLY trucks.

Have you been getting all of your fuel from the same station or have you tried different sources. Diesel with a low centane rating can hurt your mileage somewhat.

You might want to have the dealer run a scan on the injectors to see if anything shows up.

There is a long thread in the Second Generation topic discussing the disabling of the EGR valve on the LLY. Some folks have reported a fuel mileage increase after unplugging the motor.

My truck now has about 7,000 miles and I have noticed absolutely NO improvement in mileage since new. However, some have reported significant gains after break-in.

Please let us know if you figure this out.

Edited by: BH in AZ

Just recieved my '05 2500HD CC 4X4 (No mods). First 200 miles, some stop and go but the majority on highway 65-70mph, 17.2mpg. Had to stomp on it a few times for thrills!

I agree with BH. The highway mileage of 19 is about right for flat roads. I live in Illinois, so I have to stop at toll boths. This makes my highway driving seem like light city driving. I average around 16 mpg all around, but I have a hard time staying out of the throttle when taking off from a stop.


When my wife drove the truck over a weekend, she averaged 18.1 mpg and 17.8 mpg on the two fillups over mixed driving. Guess she doesn't need to accellerate like I do!

I started out in the 15-16 mpg range for highway @ 70 mph with my bone stock '04.5. First oil change it bumped to 17-18 mpg. At 10000 miles I drained everything that held lube (engine, tranny, pumpkins, transfer case) and refilled with fresh. Now I'm in the 19-20 range. Every once-in-a-tank I'll see 21 mpg. Towing my boat mpg has gone from 11-12 to 15-16 mpg.


I do 70 miles a day, 60 of it on the highway @ 70mph I buy all of my fuel from two stations (one near home, one near work) and run a tank treated with dieselkleen about every three.


I've got about 14000 on it now and I don't expect to see much more improvement so I'll be happily surprised if I do. Just give your rig some time. I'll bet you see an improvement as well. Don't be fooled by all the cry babies complaining about the fuel economy of their 7000+lb trucks that they drive like formula one cars expecting to get Honda Civic fuel economy because the dealer told them they would.

I have 900 miles on my 05 and I am getting about 16 mpg

My 04 X cab short box 4wd got 17 mpg combined driving since day one. Now at 20K it may be getting 18 mpg. That is if I keep it @ 70 mph.


My 97 powerstroke got 20 mpg!





The dealer is going to look it over, again on Friday. I think that the area rep says there is some computer reprograming to do.





Why settle for 16 mpg when sombody with a LB7 engine passes you using 20% less fuel?

I doubt if the D/A LB7's are getting better mileage than the LLY's.


At 75mph I get 19 mpg right now running a TTS Tow Tune with no cat unladen (7120lb). It got 17.5 when new, bone stock, for a 2500mi trip across the country IIRC with speeds up to 96mph in areas for extended periods.


City driving on my truck varies wildly. The more stop lights, the worse the mileage. I had one tank that was entirely city and it came to 12.5 mpg.


To really determine your highway mileage, you need to do a fairly long trip, and it has to be a round trip. Don't trust the DIC especially if you have swapped tires.


Reality is that these are VERY heavy for pickups, and stop lights or hills are going to cream your mileage, so you have to careful how you evaluate the mileage.

maybe the mileage is going down as the power keeps increasing on the diesels, what was happening 5 years ago was being done with less HP and torque, and not nearly as many mods as we make now - also, the diesel fuel was probably a lot better back then compared to now, and were talking about big heavy bad ass trucks here. I have a 4" lift with 305's and get 14.x daily around town and about 19 on freeway, towing 10k toy hauler i get about 11.x - either way im happy, could it be more, hell yeah and i wish it was but i love my truck and it gets better mileage than my last 8.1 gasser Edited by: tbone1227

Based on comparing my LLY to my brother's 2003 LB7, reading rickDlance postings about his 4 LB7's and two LLY's, and also all the other MPG posts, I would venture a guess that a good LB7 will get 3+ more MPG than a LLY.

I'm thinking mileage went down due to changes needed to meet emmision requirements. (New head, new turbo, cat, EGR, etc.)

I really doubt there's any difference between the two. My LB7 gets 19 highway ( I'm a little hard on it) and around 15 semi city. I can get as high as 21 highway if I don't burn rubber out of gas stations and keep it under 70 mph. I orig. got 13/16 when the truck was new.

Still a lot cheaper to drive than my 95 c3500, CC, LB with 454. Absolute best ever mileage on it was 12 mpg. Got a consistant 6 mpg pulling my camper. Now it is 18.5 and 13.

Mine too started out bad but is getting better with more miles according to the DIC ! Havent checked it by hand in quite awhile though. Refresh my memory , how do i calculate it by hand if Im running 265/75/16s. Isnt it take miles multiply by 3 or 3.9 % ??

This truck blows me away!!!


My last full size p/u was a '68 3/4 ton w/ 350CID engine. That was in 1978. I was pleased to get 10mpg on the highway, and ratting it around town I could literally see the fuel level drop on the gauge with one burn out.


My co-worker is pissed off at his recent Toyota purchase because of my mileage (20/15). It beats his, and I have room for my legs. I wouldn't trade this ride for anything else out there right now!

dlanderson - very well said http://www.dieselplace.com/forum/smileys/Clap.gif

Like McRat said, don't trust the DIC, especially since you've got those H2 wheels on it! I just put 285 MT's on mine and per the DIC saw about a 2mpg drop, no change in driving habits. Also when I'm going 70, the truck is actually going 76-77mph.
I run on level 3 all the time w/ the juice ***. and I'm yet to see anything below 15 mpg. But I get 15 on the highway (dont' usually drive much slower than 80 though!).

And as DLAnderson said, I wouldn't trade this truck for anything else... (unless it was someone elses modded ride on this forum! haha)


Chris

With my 2004.5 I get 20.5mpg with a very good mix of city(6mile trips)/country/and highway driving. I have about 7000 miles on it now. The first tank or two may have been slightly lower. this is with H2 wheels and BFG 285's. One tank was 75% city and i got about 18mpg


my 2003 was the identical truck with the same tires, but with the 6.0L gas and auto and i would get 13.5mpg with the same mix of driving. If i were 75% city it would drop to 13mpg.

I doubt if the D/A LB7's are getting better mileage than the LLY's.


At 75mph I get 19 mpg right now running a TTS Tow Tune with no cat unladen (7120lb). It got 17.5 when new, bone stock, for a 2500mi trip across the country IIRC with speeds up to 96mph in areas for extended periods.


City driving on my truck varies wildly. The more stop lights, the worse the mileage. I had one tank that was entirely city and it came to 12.5 mpg.


To really determine your highway mileage, you need to do a fairly long trip, and it has to be a round trip. Don't trust the DIC especially if you have swapped tires.


Reality is that these are VERY heavy for pickups, and stop lights or hills are going to cream your mileage, so you have to careful how you evaluate the mileage.
Towing is where mine is really bad. No doubt about it my LLY gets worse mileage then my LB7 did. And it is a lot worse towing close to 10,000 lbs.

I got my 2005 a few weeks ago. Now have about 1700 miles on it. Mine is a 4X4 crew cab shortbed, usually just me in it.


Don't know if I'm the exception but I seem to get really good mileage. The night I bought it I got 23mpg on the highway on the way home from the dealer with 66 miles on it.


If I reset the mpg before getting on the highway and do just flat highway 70mph driving I get 23 - 24 mpg. I'll let it drift up to 75 sometimes but usually stay right around 70. For stop and go highway mixed with 65-70 highway driving I get 17-18. I have noticed if I do 75 or 80 for any period that really starts to affect the mileage.


For stop and go around town driving I get abot 14-15 mpg.


Its still new so I try to be as smooth as possible and don't stomp on it too much (yet).


I'm coming from a 2003 5.3l Tahoe and get way better mileage with the duramax. Even if I got the same mileage as the Tahoe I'd still be happy. Way more power!

So what is the formula for figuring mileage with 265s tires on it??

Don't get me wrong, I'd be happy too if I hadn't owned a LB7 before it. The LB7 spoiled me. http://www.dieselplace.com/forum/smileys/Embarrased.gif

All these mileage post and nobody can tell me the correct way to hand calculate miles/mpg with 265/75-16s on ?http://www.dieselplace.com/forum/smileys/Confused.gif

I doubt if the D/A LB7's are getting better mileage than the LLY's.


At 75mph I get 19 mpg right now running a TTS Tow Tune with no cat unladen (7120lb). It got 17.5 when new, bone stock, for a 2500mi trip across the country IIRC with speeds up to 96mph in areas for extended periods.


City driving on my truck varies wildly. The more stop lights, the worse the mileage. I had one tank that was entirely city and it came to 12.5 mpg.


To really determine your highway mileage, you need to do a fairly long trip, and it has to be a round trip. Don't trust the DIC especially if you have swapped tires.


Reality is that these are VERY heavy for pickups, and stop lights or hills are going to cream your mileage, so you have to careful how you evaluate the mileage.



Towing is where mine is really bad. No doubt about it my LLY gets worse mileage then my LB7 did. And it is a lot worse towing close to 10,000 lbs.


You might consider a "tow tune". We got between 11-12 mpg at 17,000lb combined (11.5' camper, car trailer) at 75mph typical speed for 5000 miles. Lots of mountains. I consider that very good mileage consider the weight, speed, and the large frontal area of the camper. My gas E-350 at 12,000 combined got 7-8 mpg with similiar frontal area at 60 mph.


While I did not test the mileage towing without the tuning, the fact the truck seldom ever shifted out of 5th probably saved a lot of fuel. Even in the mountains, the only time it downshifted was when I wanted to pass and made it downshift.

I fully expected there to be a drop in mileage due to the placement of emission controls; there always is.


I suppose I could have looked for a used LB7 and possibly kept a couple/few more miles per gallon. But, I wanted a new truck so it was to be the LLY. It beats gas any day of the week; power, mileage. My Sierra beats the Suburban in cost per mile by about 20%. For that I am happy indeed.


In a more utopian world we would not be burning diesel made from oil, but peanuts like Diesel himself did (or Corn, Soy Beans, or rotting fruit even). Then we could tell OPEC to take a hike, aid the farmers and our own economy. I am sorry... Starting to preach, or Speech, or Leach - Things that none of you are here for.

Maybe if the government would push for a reasonable alternative fuel like organic oils you could burn in a diesel we could get to where you want to be. Not going to happen when they push for more 'glamorous' stuff like pie in the sky technology like hydrogen...


Sorry, didn't mean to hijack....

You might consider a "tow tune". We got between 11-12 mpg at 17,000lb combined (11.5' camper, car trailer) at 75mph typical speed for 5000 miles. Lots of mountains. I consider that very good mileage consider the weight, speed, and the large frontal area of the camper. My gas E-350 at 12,000 combined got 7-8 mpg with similiar frontal area at 60 mph.








If you had an LB7 you would be getting better (towing). I bet you would get 20% better or more. No kidding.Edited by: Max Power

On the way home the other night on the interstate I got 33 mpg with my 6.0 for about 10 miles..............http://www.dieselplace.com/forum/smileys/Big Smile.gif http://www.dieselplace.com/forum/smileys/Big Smile.gif http://www.dieselplace.com/forum/smileys/Big Smile.gif

Come on guys ,there are just too many inconsistencies here, I'm sorry but I find it hard to believe anyone is getting 21 - 23 mpg "consistently" forget the DIC (although mine has been right on) and run a full tank and calculate the mileage by hand.

My 03 D\A LB7 got 16 - 17 mpg and never broke 18 mpg in the 20,000 miles I owned it.



For calculating the mileage with 265s add 3% to the miles your speedometer shows you traveled since the last fill up and divide by the number of gallons to fill back up.

For calculating the mileage with 265s add 3% to the miles your speedometer shows you traveled since the last fill up and divide by the number of gallons to fill back up.


Thanks Steve, i was beginning to think i was invisible. LOL


My old LB7 w/245s got 22mpg "one" time going 65 on flat land and driving like grandma . On a long trip to Colo. it got like 19.8 going 75-78 but cant remember which tires i think they were still the 245s. This seems to be in line with what most are saying.


I have yet to see those #s out of my LLY but it does have 265s on it and Im just now getting some miles put on it. At about 4000mi i hand checked it and got like 17 going about 70mph. We are up to 14,000 mi now and the DIC is showing better #s for what it is worth. Now that i now how to hand calculate it again i will start checking again. Thanks again !

All my numbers above are hand calcs..no DIC to go off of


I ran 100 miles on the highway per the milage posts on the side of the road and divided that into what my odometer said for the same distance. it is about 8.3% off with the 285's at the pressures that i am running


another note:


2004 LB7 running off-road diesel 60 year old farmer running country roads (45mph). identical truck to mine except stock wheels/tires..routinely gets 24mpg

My last tank gave me 26 mpg w/some Chicago city driving, most of the tank was 70 mph. My best was 30 mpg at 75, all interstate. Do you suppose the propane has something to do with it?http://www.dieselplace.com/forum/smileys/HiHi.gif

marcdeluca,

You make Hank Hill proud http://www.dieselplace.com/forum/smileys/Big Smile.gif

Steve Cornell,


I don't see anyone here who said they are getting '22-23 miles consistently'. Pepole are quoting different numbers based on different driving conditions.


I'm getting really good mileage as I posted earlier. The numbers I gave came from the DIC. I've verified the DIC with hand calculations and my DIC is accurate.


For the different numbers I quoted if specified the specific driving conditions to show what I was getting under those specific conditions. If you want to compare your mileage to someone elses to see how yours compares you need to take into consideration the different driving conditions, right? You have to compare apples to apples.


If I just said 'on my last tank of gas I got 18mpg' that would be pretty meaningless to someone who wanted to compare their mileage to mine. To do a good comparison of my truck to theirs they would have to drive the same way as I did for that full tank of gas.


If I reset the counters and drive for a while under specific conditions to see what I get, someone can do the same to see what they get.


Mark

For calculating the mileage with 265s add 3% to the miles your speedometer shows you traveled since the last fill up and divide by the number of gallons to fill back up.





My math says it 4%. Different tire size calculators on web also indicate that.

marcdeluca,

You make Hank Hill proud http://www.dieselplace.com/forum/smileys/Big Smile.gif


Who is Hank Hill?

Hank Hill - King of the Hill on Fox. Never seen it? He is a propane salesman and propane is his life! Show is funny as heck. Check it out.

If you go by the numbers, the circumference of a 245\75\16 is 95.718" and a 265\75\16 is 99.428" so yes it is closer to 4% than 3% but because of different tires the really only way to tell for sure is to do a "roll" test, with the tires on the truck and weight on the tires strike a chalk line across the tire and roll the truck and measure the distance between the line marks on the pavement \ concrete, this would need to be done with both size tires to get the "exact" measurements.

On my 03 DA I replaced the stock 245 Bridgestones with 265 Michelins and the difference came out to 3% and several people on this and other forums have confirmed that 3% is close via GPS as well.

I will say that my CC LLY shortbed was getting pretty bad mileage when I first got it, seemed it was all about how much foot I put into the petal. I was also trying to make up for the turbo lag - it seemed I didn't have enough or too much. Now I know the truck, it has 4k on it and the mileage gets better all the time. Is it the motor breaking in, maybe. Is it me getting used to the motor, maybe. I don't know. It gets 14-15 in stop and go traffic (Seattle), I only drive in traffic it seems (to and from the office). But on the freeway, it gets 19-20. Granted I am going by the DIC no hand calcs. But I do have larger tires so I would assume that my DIC would be showing lower #'s than reality? Anyway, now I am used to the turbo lag (it seems to have gotten better), I know when and how to use the power and all is well. I am with the guy who said, this is an over 7000# vehicle, don't expect too much here guys. I know the LB7 was great, but everything does and always will change. The LLY could be worse.

My ole 62 Ford got 34 miles to the gallon with our six kids, the dog, and pet pig in back at 90mph with the windows down and a little vinegar added to the ole gas tank! http://www.dieselplace.com/forum/smileys/hihi.gif


Confucious say "There is direct correlation between ability to keep one's foot out of pedal and ability to slow ass down". http://www.dieselplace.com/forum/smileys/hihi.gif


Chief JJ say "drivem big truck, much power, wampum other trucks, much fun!"


Screw the mpgs, drive em boys! JJ's out! http://www.dieselplace.com/forum/smileys/smiley4.gif

I got 21 mgp on one tank one time. I wish I knew how or why. 18.2 is what I seem to get on a pure highway trip or late. I have a lifetime average of 15.6. I did see a loss when I went to 265s and I have corrected the speedometer from the start of the change with the Preditor. Still better than the 12-13 I got on my old gasser and WAY better than the 11 my wife gets on her SUV. I find it interesting that I get 15 in town and 18 on the hwy. I have gotten 19 two or three times, but not consistant. I was expecting a little better, but it's not bad enough to worry about.


Does everyone see a mpg increase using propane? I might be able to use that to sway the wife if it is pretty repeatable. http://www.dieselplace.com/forum/smileys/smiley2.gif

Now I have a lb7 04 cc 2WD. I check by hand and get 18.5-19mpg every day driving. Trip to Tenn. no trailer 21mpg. Even I cant believe it. Have done only one trip with trailer, short trip, and a lot of lights, 6000lbs unit got 13.5. I am one happy camper!

I will have had my '05 two weeks tomorrow. Currently 825+-
miles. Not including the fillup the dealer did upon delivery I have
filled it three times.



First tank was 16.0 MPG on the DIC and 15.1 calculated. Second was 15.6
on the DIC and 14.3 calculated. I filled up for the third time this
afternoon and DIC indicated 15.5, calculated was 14.3 once again.



I have only four complaints so far

:

1) Fuel economy a little lower than I anticipated. But - a bunch better
than my '02 6.0 4L80E 4.10 Crew Cab - which under similar driving
conditions usually returned a calculated 11.5 MPG!


2) Terrible ride - already fixed by installing KYB MonoMax front shocks
and adding weight to the rear with a 60# Rhino liner and a #664 Weather
Guard aluminum chest with about 150# of crap in it. It now has the BEST ride of any GM pickup I've owned for at least 20 years!


3) Tiny OEM tires. Still haven't decided what to do about that one yet.
I have a set of H2 wheels, but unsure of what 17" LT rated tires to use.


4) Turbo lag from a dead stop that almost killed me the first time I
experienced it. Still trying to acclimate to driving a turbo diesel.




Edited by: Lloyd-TX

Getting ready for a short road trip so I filled up again this morning:



16.3 MPG on the DIC and only 14.6 calculated! DIC accuracy stinks so far!

my stock 1 week old 525 mile truck is getting 18.6 per the DIC(majority hiway). Once filling the tank, I can check the DIC accuracy. Edited by: sc3283

Just came back from a run up Lamoille Canyon. Got 7 mpg one way and 99 mpg on the return. What gives???? Overall this 2004.5 is getting 17.5 mpg, not good, not bad but the A-Rabs still love me.

Just came back from a run up Lamoille Canyon. Got 7 mpg one way and 99 mpg on the return. What gives???? Overall this 2004.5 is getting 17.5 mpg, not good, not bad but the A-Rabs still love me.


Is the trip to the Canyon uphill 15% the whole way? I suppose a Dmax idling on the return trip at 70 mph could return 99 mpg!

Just got the 05 2500 4X4. When I drove it off the lot with 14 miles on it I was at about 12.3 mpg on the highway. I now have 348 miles and I am avaraging 16.7 mpg mostly mixed driving. I still have a grin on my face driving it around http://www.dieselplace.com/forum/smileys/smiley4.gif