|
Duramax MPG Thread
I've heard that 23 highway in a 4x4 is easily attainable with exhaust and the right tune. Is this right? Can it go higher?
|
sounds about right
|
yeah it is, the guy in last years diesel power challenge hit 23 or 24 im almost positive. alot has to do with your drivin style too.
|
That's impressive. I guess a guy would have to stay at 60 to make it happen though....
|
in either diesel power mag or diesel world i cant remember which one, but they got a 12v cummins to get like 28 mpg. now mind you they duct taped the every hole on the truck, blocked off the radiator to make it run hotter, folded in the mirrors and didnt run ac. they did other things to but you get the idea
|
I would think that 24 is pushing it. 20-21 seems more realistic but on the internet there is no telling what someone will post.
I just topped my truck of with 24.7 gallons of ulsd and had 257 miles on the trip =10.40 mpg not hot rodding, in fact almost all highway. |
i heard tommy got 27.2 mpg with his LMM for the diesel power mpg test
|
Originally Posted by 2500HeavyDuty
(Post 169773)
i heard tommy got 27.2 mpg with his LMM for the diesel power mpg test
|
he had his dpf removed and his race 530hp tune, the speed ranged around 55-65
|
I don't think I've heard of many autos getting over 23MPG manuals do a little better. I can get 21MPG with 85% Hwy driving in town and think I was getting the same on the open road at 75MPH. I'd say your doing ok at 20MPG or better some never see over 18. This is only true with the pre-PDF trucks.
|
my truck is stock and empty and driving sane i get 650 - 750 miles out of a tank
i use diesel clean with cetane boost every tank(in the grey bottle). and my rig aint no reg cab short box on secret is to keep your mass air flow sensor clean i use a good carb cleaner i do that every oil change. make sure it evaporates and doesn't leave any deposits |
oh yeah, the MAF is very important to keep clean,
it can be a real hassle if you have an oiled aftermarket filter. it can cover the sensors with oil and your MAF will give false readings back to the ECM. End result extreme turbo lag and loss of mpg, and not as responsive. |
have a tube that keeps coming off like mine i need to find a new intake tube that is either longer or get new boots that are longer i have to check mine almost everyday. you could try what this guy does its called hypermileage i saw a clip on a show about this once they used a that little Pontiac sports car
|
24 is really pushing it. 27?? NO WAY. The only way that happened is that he was driving down a mountain. I average 21.5 on the freeway at 75 mph and 15 in town. I sit in traffic for 2 hours a day so my in town mileage is going to be low. 650-750 on a 26 gallon tank. NOT HARDLY. You're trying to tell us that your getting 25-29 mpg??? Might wanna call GM...you've just performed a miracle. :crack:
|
Not to jump on the bandwagon, but I have to agree. Even with stock tires, 27 is not going to happen. Double check and hand calc your #'s. If you found a way to get 27 with real world driving, you will be wealthy very soon when you sell your secret.
|
how many of you every driven at 55mph for a long time, i know it hard, but it could increase mpg.
I just cant live that slow to find out for myself |
Just a note:
A while back, some people were jacking around with high MPG tunes and saw increadable numbers :U: BUT melted a few pistons in the mean time :booo: Just an FYI.......:ph: |
im good with 20, dont need more than that myself
|
My 03 LB7 gets 22-24 mpg with about 20% in town driving at 70-75 mph. Pulling a 40 ft trailer empty is 15-16 and loaded grossed out at 45k it gets just over 10.
I have 5in straight exhaust and other than that I have no other upgrades. I do use a additive called Howes Meaner Cleaner, which I swear by. Maybe the 6-spd helps out a little too. |
Originally Posted by DangerousDuramax
(Post 188337)
24 is really pushing it. 27?? NO WAY. The only way that happened is that he was driving down a mountain. I average 21.5 on the freeway at 75 mph and 15 in town. I sit in traffic for 2 hours a day so my in town mileage is going to be low. 650-750 on a 26 gallon tank. NOT HARDLY. You're trying to tell us that your getting 25-29 mpg??? Might wanna call GM...you've just performed a miracle. :crack:
|
longbeds are better anyway :dd:
|
You know it.
|
this guy in diesel power got 38 but he was using propane so i dont think it counts
|
tommy hit 27mpg with his lmm and a bigger turbo
|
yeah i saw that too but that was at 55-60 MPG and his turbo was only making 2 PSI of boost
|
u mean 55-60 mph, what a difference when u drive slower eh?
|
My DIC tells me I'm getting 99mpg when I'm coasting downhill :downlow::rolleyes2:
|
i went 50 MPH for 2 miles on the higway the passast said i was getting 45.2 MPG andi was so bored so i said screw it and kicked it up to 75-80 MPH and MPG went down to 37.5
|
i do all my figuring myself, u cant count on the computer.
|
I have to post in this one, my truck on the highway averages a "Varifiable" 24.5mpg when I keep it set right on 70,, however, I DO have a manual tranny, and I do feaththe throttle for acceleration, and when on the "Big Road" I put maximum pressure in the tires. On a trip this summer to my mom's house at the beach on OAk Island NC, 351 miles from my driveway to hers, I used 14.32 gallons of fuel. I filled up and then went home and got packed and left, other than acceleration, and the fact that we started out @ 3AM to take advantage of less trafffic, my overall average mph was 63, and that is including highway and secondary roads and all. SO, 351 miles / 14.32 gallons = 24.51117318 mpg on the trip. :U::rocking:
OH, I forgot, I filled the tanke to the top of the filler neck before and after the trip to get an accurate, "hand calculated" measurement... the only thing that may have thrown the measurement off is the size of my tires, but I am not real sure how to make the adjustment for that., if anyone can take my calculations and make the adjustment to account for 285's tire size and then let me know I would appreciate that... and let me know how you make it... |
yeah i dont count on the computer becayse it is a average of what im doing. if its a regular week im getting somewhere in between 35-37 MPG but on a trip to arkansas i took on the highway i got 42 MPG once. i dont get as great mileage as a jetta because i got bigger car and bigger engine and now i will shut up because i just hijacked the thread
|
Originally Posted by bigdaddydiesel
(Post 191877)
I have to post in this one, my truck on the highway averages a "Varifiable" 24.5mpg when I keep it set right on 70,, however, I DO have a manual tranny, and I do feaththe throttle for acceleration, and when on the "Big Road" I put maximum pressure in the tires. On a trip this summer to my mom's house at the beach on OAk Island NC, 351 miles from my driveway to hers, I used 14.32 gallons of fuel. I filled up and then went home and got packed and left, other than acceleration, and the fact that we started out @ 3AM to take advantage of less trafffic, my overall average mph was 63, and that is including highway and secondary roads and all. SO, 351 miles / 14.32 gallons = 24.51117318 mpg on the trip. :U::rocking:
OH, I forgot, I filled the tanke to the top of the filler neck before and after the trip to get an accurate, "hand calculated" measurement... the only thing that may have thrown the measurement off is the size of my tires, but I am not real sure how to make the adjustment for that., if anyone can take my calculations and make the adjustment to account for 285's tire size and then let me know I would appreciate that... and let me know how you make it... |
Originally Posted by dozerboy
(Post 191253)
Maybe he has a long bed with the 34 gal tank
|
thanks...
Originally Posted by DangerousDuramax
(Post 191937)
If you havent corrected your speedo all your hand calculations are off because your mileage isnt correct.
ie: the mention of the fact that they were off due to tire size... but thanks for the effort... ok, according to mapquest the actual mileage would be 330.95, using14.32 gallons = 23.11mpg |
correct me if im wrong, but i believe you take size of tire 33 = 285/stock 245=29.79 is 1.10775 (rounded off) 351x1.10775=388.82 that would make for 27.15 mpg, no way? i believe thats a correct calculation, read it years ago and i think thats how it was done.
|
from 235 to 285 is around 11%
|
Hey everyone, I am new to the forum. Well after reading all of the threads related to the Duramax fuel mileage, I can't help but feel that I am missing something and I need some education from all of you to help me out. I have an 05' Chevy Silverado 2500 HD 4WD Crew Cab Std Bed w/ 6.6 Turbo DMax. Truck has a 4" lift with 305 70/16 tires. I have an aftermarket AirAide system with an oil bath filter. Otherwise than that everything else is factory original. Most of the miles that I put on my truck are highway miles. I average approx. 140 miles/day on the highway and I am only averaging, when I am on my best behaviour, about 13.9 miles/gl. What could be the problem, or does this sound about right? :humm:
|
Originally Posted by DangerousDuramax
(Post 191938)
uuumm....John....the fuel consumption of the engine has nothing to do with the size of the tank. :rolleyes2: He still isnt getting over 24 MPG now matter if he has a 5 gallon tank or 100 gallon tank. :dd:
i use diesel clean with cetane boost every tank(in the grey bottle). and my rig aint no reg cab short box on secret is to keep your mass air flow sensor clean i use a good carb cleaner i do that every oil change. make sure it evaporates and doesn't leave any deposits 2003 duramax crew cab long box straight pipe exhaust AEM brute force intake Readylift leveling kit and a Striker)...............so with that being said a long box has a 34 gallon fuel tank stock. So then with simple math you take 650 divided by 34....and that equals 19.117647. or take 750 divided by 34.....and that equals 22.058823. to me that kind of mileage is pretty average as everyone else in this thread has said many times. So tell me how your math he is getting over 24mpg????? And tell me how when you are calculating an AVERAGE OF MILES PER GALLON, tank size has no affect on the outcome????? ---AutoMerged DoublePost---
Originally Posted by DangerousDuramax
(Post 191938)
uuumm....John....the fuel consumption of the engine has nothing to do with the size of the tank. :rolleyes2: He still isnt getting over 24 MPG now matter if he has a 5 gallon tank or 100 gallon tank. :dd:
|
Originally Posted by truckin38s4x4
(Post 735553)
I dunno how YOU calculate fuel mileage unless you use the dash.....not a bright idea.....but usually you take the total mileage divided by the amount of fuel in gallons and it gives you an AVERAGE of MILES PER GALLON. So if you read his thread is says............... (my truck is stock and empty and driving sane i get 650 - 750 miles out of a tank
i use diesel clean with cetane boost every tank(in the grey bottle). and my rig aint no reg cab short box on secret is to keep your mass air flow sensor clean i use a good carb cleaner i do that every oil change. make sure it evaporates and doesn't leave any deposits 2003 duramax crew cab long box straight pipe exhaust AEM brute force intake Readylift leveling kit and a Striker)...............so with that being said a long box has a 34 gallon fuel tank stock. So then with simple math you take 650 divided by 34....and that equals 19.117647. or take 750 divided by 34.....and that equals 22.058823. to me that kind of mileage is pretty average as everyone else in this thread has said many times. So tell me how your math he is getting over 24mpg????? And tell me how when you are calculating an AVERAGE OF MILES PER GALLON, tank size has no affect on the outcome????? ---AutoMerged DoublePost--- I really want to know how you calculated OVER 24MPG without using the size of the tank in the calculation?????????????? John has 38's on his truck, his is not calibrated for 38's. so if he used the trip odometer to calculate, it will be thrown off. you dont need to know the size of the tank to calculate mpg, as long as you fill it up to the top, then look at the fuel pump and see how much fuel you put in and divide it into your trip meter. |
I would definitly have to agree with you on that. But in the original post the guys states 650-750 miles to a tank. doesnt ever mention how many gallons he put in his tank from the pump. so with that in mind a rough average would have to be calculted by the size of the tank or close to...so a 34 gallon tank...using round numbers 30 gallons used if you wanna push it that still is no where near 25-29 mpg. i definitly agree with you. im quite content with 18 in my truck as well
|
| All times are GMT -5. The time now is 09:26 PM. |
© 2024 MH Sub I, LLC dba Internet Brands