3rd Gen RAM general discussion/NON-tech This section is for general discussions about your 3rd gen RAM. Non tech related RAM threads belong here.
Old Aug 5, 2015, 12:02 PM
How-Tos on this Topic
Last edit by: IB Advertising
See related guides and technical advice from our community experts:

Browse all: General Overview
Print Wikipost

How to Improve Gas Mileage in 5.7l HEMI?

Old Apr 13, 2012 | 03:02 PM
  #11  
HammerZ71's Avatar
HammerZ71
Administrator
Joined: Jul 2007
Posts: 24,686
Likes: 21
From: South Georgia/East Florida
Default

Since my efan was one of the few mods I did by itself it's one of the few I could fairly accurately tell how much the benefit was. Pure in-town driving was pretty consistently 1.5 - 2 MPG gain, while pure highway was a non-factor, maybe a small percentage of an MPG gain. Over-all driving for me sees about 1.5 MPG better PLUS a notable improvement in acceleration from a stop without the parasitic clutch fan...
 
Reply
Old Apr 13, 2012 | 03:06 PM
  #12  
HammerZ71's Avatar
HammerZ71
Administrator
Joined: Jul 2007
Posts: 24,686
Likes: 21
From: South Georgia/East Florida
Default

Originally Posted by crazzywolfie
man hammer. i think you are getting a bit forgetful. what about that startron stuff you are always preaching about for all the people that can't find ethanol free pumps?
Although I do see a decent gain in MPG, I really don't have enough proof at this point to make a recommendation based solely for MPG gains. I will swear that my engine runs smoother as it takes out the nasty effects of ethanol.
If I am going to say "do or buy this and you'll get better fuel economy", I want to be able to back it up that it works EVERYTIME for EVERYBODY...
 
Reply
Old Apr 13, 2012 | 05:29 PM
  #13  
crazzywolfie's Avatar
crazzywolfie
Legend
15 Year Member
Liked
Joined: Jun 2009
Posts: 8,025
Likes: 72
From: orangeville ontario
Default

the guys in the 2nd gen section seem to have good results with it or you could try filling up with ethanol free gas. according to my fuelly account if my 81 was to gain only 1 mpg i would save $8.99 which would pay the difference of using the 91 octane gas that is ethanol free.
 
Reply
Old Apr 14, 2012 | 12:05 AM
  #14  
Catchin Zs's Avatar
Catchin Zs
Professional
Joined: Nov 2011
Posts: 178
Likes: 0
Default

Hmmm... buy a Prius.
 
Reply
Old Apr 14, 2012 | 02:20 AM
  #15  
thumperk15's Avatar
thumperk15
Veteran
Joined: Aug 2008
Posts: 319
Likes: 0
From: Fort Smith, AR
Default

I have yet to see a mileage gain with Startron. I'm averaging 14.5mpg on the last 3 tanks. 320 miles on 22 gallons. I don't like the gas prices but no way in hell I'll trade my hemi for a gas sipping Chevy, they can average like 19-20, I'll keep my 14.5. Note: my truck overhead always says like 15.5-16.5 and I'm 14.5 every tank. I do have 24's, and I like to hear my engine roar a lot too lol. I always say "next tank I'll drive easy", well I have yet to let gas prices make me drive an awesome sounding engine slowly. If I give in I may as well buy a Smart Car, and sell my ********* lol. I'm a man and I'll drive a mans truck! With all that said I think you should calculate the gallons you use from fill tank and be happy, you have a HEMI!!!
 
Reply
Old Apr 14, 2012 | 11:05 AM
  #16  
Chet Ubetcha's Avatar
Chet Ubetcha
3rd Gen Ram Moderator
Joined: Jul 2005
Posts: 1,596
Likes: 16
From: Cádiz, Spain
Default

Kind of funny about the Smart Car. I was picking up my daughter from school a while back, and as I was walking up the sidewalk to the parking lot, a little Smart Car pulled out from the other side of my truck. The thing completely disappeared on the other side there, and didn't even come up to my hood. I just saw this little thing roll out from my front bumper. It was actually kind of comical at the time. Don't knock Smart Cars, though. They were never designed for the American market/roadways, but fit their niche quite well in their natural habitat...

With class in the middle of the day now, I am no longer making two 20-mile round trips a day to and from my daughter's school. I just stay on base all day after dropping her off, therefore theoretically cutting my daily/weekly mileage by roughly one-half. I'm experimenting with my driving style right now trying to see what kind of throttle responses generate the best results, mileage-wise, on all these hills. I've been driving like a grandma trying to keep my RPMs below 2K as much as possible, and optimally as close or under 1,500 as I can. I'm getting pretty good fuel results, but Mudder O'Gawd DRIVING LIKE THIS IS KILLING ME!
 
Reply
Old Apr 14, 2012 | 01:52 PM
  #17  
hillbilli's Avatar
hillbilli
Veteran
Joined: Jun 2011
Posts: 284
Likes: 0
From: ND
Default

Tuners are nice for towing on the 03's because there is no tow/haul mode for the tranny. Used to have a Superchips tuner on my 03 1500 and 2500. It mabey gave a slight bump on the 1500, but not a damn thing for the 2500, just too heavy of a truck. Even on the durango, with MDS it really wasnt a noticable gain for mpg. Ethanol free gas, proper tire inflation, and a light right foot are probably the best things.
 
Reply
Old Sep 10, 2012 | 03:41 PM
  #18  
SmogCop's Avatar
SmogCop
Registered User
Joined: Feb 2012
Posts: 2
Likes: 0
Default

Here's hoping that someone will have some advice.
I have scanned several sites and lots of Dodge forums regarding fuel mileage on my 2005 Dodge Ram STI Quad Cab 5.7L Hemi. I replaced the platinum plugs that the previous owner installed with Champion Copper Plus, I changed the air filter (stock), pulled the throttle body and cleaned off the caked on carbon and wiped out what I could reach of the intake. I stopped using 87 octane fuel and filled up with 91 at half a tank. I am into my second half tank of 91 (cheaper at Sams Club than 89 at most other stations). My mileage is still 9-10 city and about 12-13 highway. Several things I have noticed. When I start the truck and immediately put it in gear the trans slips (hot or cold doesn’t matter). If I wait 30 seconds then put it in gear all seems ok. No other slippage noticed. After that 30 second wait time I put in gear and drive say 20 feet (end of my driveway) the truck stumbles and sometimes stalls, usually only cold but occasionally hot.
Anyone have any constructive thoughts?
 
Reply
Old Sep 26, 2012 | 11:55 PM
  #19  
Mneuls's Avatar
Mneuls
Registered User
Joined: Sep 2012
Posts: 1
Likes: 0
Default

I drive a 2010 dodge ram 2500, i use it for work, carrying around 600-1000lbs of parts/tools/equipment at any given time. When bone stock, i got around 11mpg, with tow/haul on, i could manage 12.5, but noticed a braking effect on hills, and couldnt coast properly. A few months ago, I installed a flowmaster cat-back, an afi intake and a diablo trinity tuner, all at the same time. I tuned it for the mpg saver mode and adjusted the shift points up a bit, almost like a tow/haul type setup. I have been getting around 15mpg average since. I spent $23,000 on fuel last year, with my new fuel economy, based on a similar travel as last year, i should save $3000 or more, doubling my investment within the year, (hopefully). I just installed the e-fan tonight (super easy) and im looking foreward to a bit extra fuel savings. Ill post mpg gains, if i see any. (not interested in Power gains)
 
Reply
Old Sep 27, 2012 | 01:52 AM
  #20  
GoManGo420's Avatar
GoManGo420
Registered User
Joined: Apr 2010
Posts: 3
Likes: 0
Default

I installed headers and my hwy mpg increased from 17-18 to 20-22 average. Also used a can of stp type seafoam in a full tank of gas.

Mods are intake, headers, exhaust, diablosport 91 tune.
 
Reply

Thread Tools
Search this Thread

All times are GMT -4. The time now is 01:17 AM.