Hello:

I have a Chevy 2007.5, 2500, 4 door, 4X4 with 285's and 4000 miles. I am trying to improve the MPG from about 14.5 mixed city/highway to as good as I can get it cost effectively. It already has enough power to pull my travel trailer, so saving some dollars is now the priority.

Question #1 - is there some list of acronyms so I can figure out what you guys are talking about. Example - I can't figure out what LMM means and I am pretty sure I own one. :) I don't have a prayer on some of this other stuff.

Question #2 - from what I can gather it sounds like I need a new, air filter, exhaust system, and tuner or chip. If I do these things could I get a 4+ MPH improvement?

Thanks a bunch

1- LMM is the platform or series of duramax engine you have

2- the air filter is pretty good in stock form as for exhaust there are allot of members here scrapping the whole thing and running the old style from the classic models as well they are putting them on from DPF Back. as for the programmer i would think someone else will chime in because i havent decided which to buy yet but i am leaning towards the PPE.

3- DPF- Diesel particulate filter

Hello:

I have a Chevy 2007.5, 2500, 4 door, 4X4 with 285's and 4000 miles. I am trying to improve the MPG from about 14.5 mixed city/highway to as good as I can get it cost effectively. It already has enough power to pull my travel trailer, so saving some dollars is now the priority.

Question #1 - is there some list of acronyms so I can figure out what you guys are talking about. Example - I can't figure out what LMM means and I am pretty sure I own one. :) I don't have a prayer on some of this other stuff.

Question #2 - from what I can gather it sounds like I need a new, air filter, exhaust system, and tuner or chip. If I do these things could I get a 4+ MPH improvement?

Thanks a bunch
:welcome:

I'd keep the stock filter element. It breathes extremely well + the filtration level is second to none.

As far as improving your MPG....There have been a number of guys that have removed the DPF and/or straight piped their trucks and tuned with EFI Live to delete the codes that you will get when removing the DPF. All of them have jumped up their MPG.

I'd pay attention to this forum and the "Power and Performance" forums to see what others have done to increase their MPG's. Good luck in your quest.

I agree with everybody about the factory air filter, just to the air box mod. As for exaust, do the MBRP, or equal, filter back or you will have to deal with the check engine light and maybe limp. PPE for the programer. I like mine and gives great power. They are also comeing out with the DPF delete, then do full exhaust. My truck form the factory was getting 17mpg on the first 300 mile trip. Now I get 21 on the same 300 mile trip and I average 16 on my daily driving in town and out. I also have a heavy foot.

The 285s you are running are not going to help with the hunt for mpg. Some guys have reported a 2mpg loss going to 285s, so my first recomendation would be going back to 265s if mpg is more important than looks. Second would be keep your' foot out of it, that is the biggest factor in mpg. A turbo back exhaust, tuning, and other add ons will make a big difference, but not as big as you yourself can. Make sure to keep the rpms under 2000 and speeds under 70, I'm sure you'll see a difference. There does seem to be a difference from truck to truck though, I would have to try real hard to get 14.5mpg. The worst I've ever seen out of my truck was 16.4mpg when it was brand new and saw mostly city driving. It just seems to get better and better too; this last fill up I beat the hell out of it with a day at the track, stupidness on the street, burnouts and alot of time on the speed limiter - DIC reads 17mpg:D . Truck is totaly stock with 265s and I usually get 18-19 hand calculated out of it. Can't wait to ditch the DPF, tune it and try n get 22 out of it!

The best solution I have found for MPG improvement is 65MPH Max. I know it sucks, but it works.
Being humble is going 65 with a Duramax. O Lord, Its hard to be Humble!

I live in Texas and you have to get an inspection every year. If you ditch the CAT and DPF that makes the truck unable to pass inspection right. So is the going to be an ongoing thing to have to put all the emissions equipment back on every time you have to get an inspection on the truck so that you can pass a state inspection and renew you registration. How are the guys in Cali getting away with this because I know y'all have some tough emission laws.

stock 265's here and can get 21 to 25 on highway at 70, drafting :) and 19-20 not drafting and going 73mph

State inspections are one thing, but you also should be aware of warranty issues when tuning your truck. GM can void the engine warranty if they find aftermarket programmers, chips or whatever mods. My '04 LLY didn't start getting decent mileage 'til the engine was well-broken in, say 15,000 miles or so. Maybe yours is the same. I'd give it some time before throwing a lot of cabbage around to try and gain 3-4 mpg.

Try the hypertech max enery tuner....i tested one out and pulling 12k pounds at 70mph i saw up to a 2mpg improvement over stock...thats on level 2....

Wow guys thanks for all of the info.

I should have asked first, but I just ordered a K&N air filter form Cabelas. Should I call and cancel?

Is the back pressure on the exhaust system a big deal? I have been talking to big truck guys and they act like it's a big deal.

Any thoughts on the Bully Dog Power Pup? There is a place by my house that will let me down load it for free for 4 hours. I would prefer to try before I buy.

How do I recalibrate the mileage by going from 245's to 285's? I may be getting better milage than I think?

I rarely get on it, but I may be running a little fast due to the bigger tires. I need to figure that part out.

Thanks again.

Cancel your order on the K & N!!! They are junk!!

return the k&n for sure every one here has had nothing but issues with it a programer will reprogram your tire size or the delaer can do it for you to

I live in Texas and you have to get an inspection every year. If you ditch the CAT and DPF that makes the truck unable to pass inspection right. So is the going to be an ongoing thing to have to put all the emissions equipment back on every time you have to get an inspection on the truck so that you can pass a state inspection and renew you registration. How are the guys in Cali getting away with this because I know y'all have some tough emission laws.

ROVPILOT, here in Cali, currently diesels are exempt from SMOG inspections. That doesn't mean it won't change in the future. I don't think we have a lot of diesel vehicles/cars/pickups here in California but that may change with all the new diesel emissions stuff. California, for years, has made it difficult to own diesels with high diesel prices and lack of diesel stations. Recently though I'm starting to see a lot more local diesel stations. (JMO, subjective of course)

-Ronnie

Wow guys thanks for all of the info.

I should have asked first, but I just ordered a K&N air filter form Cabelas. Should I call and cancel?

Is the back pressure on the exhaust system a big deal? I have been talking to big truck guys and they act like it's a big deal.

Any thoughts on the Bully Dog Power Pup? There is a place by my house that will let me down load it for free for 4 hours. I would prefer to try before I buy.

How do I recalibrate the mileage by going from 245's to 285's? I may be getting better milage than I think?

I rarely get on it, but I may be running a little fast due to the bigger tires. I need to figure that part out.

Thanks again.

There's lots of tire calcs out there on the internet and there's been several threads, I believe, in the Wheels & Tires section with good info. Anyways, the difference between the 245/75R16 and the 285/75R16 is approximately 7.20%. If your speedo is not adjusted for the larger tires, then take your speed and muliply it by 7%. That will give you your actual speed. Also, you can take your trip and multiply it by 7% and that will give you your actual mileage. I.E. your DIC shows 300 miles on the trip. Take 300 x 1.07 = 321 actual miles.
Hope that helps.
-Ronnie

If you have not reprogrammed for your tire size your millage on your DIC will be off!

Do the mod to your stock air box, its twice as better than the K&N.

Try the hypertech max enery tuner....i tested one out and pulling 12k pounds at 70mph i saw up to a 2mpg improvement over stock...thats on level 2....


what do you get empty?

with the tuner on level 2.....if i maintain similar speeds and can keep my foot out of it......19-21mpg highway...16-18 city.....15 when I am in a hurry

check out this thread...i have a mileage report on page 2...

http://www.dieselplace.com/forum/showthread.php?t=184588

How do you mod the air box?