3rd Gen High Performance and Accessories (5.9L Only) Talk about Dodge/Cummins aftermarket products for third generation trucks here. Can include high-performance mods, or general accessories. THIS IS FOR THE 5.9L ONLY!

How come I can only get 14.9 mpg

Thread Tools
 
Search this Thread
 
Old 09-14-2008, 07:41 PM
  #1  
Registered User
Thread Starter
 
cowboy2526's Avatar
 
Join Date: Jul 2008
Location: Godley, Texas
Posts: 182
Likes: 0
Received 0 Likes on 0 Posts
How come I can only get 14.9 mpg

Should I not be getting more mpg's than this I dont do alot of city driving, I have 3.73's.
Old 09-14-2008, 07:52 PM
  #2  
Registered User
 
megacabdad's Avatar
 
Join Date: Jul 2008
Location: Erie, PA
Posts: 2,731
Likes: 0
Received 0 Likes on 0 Posts
I'll assume you are talking about the '07...and are hand calculating?

What type of tires are you running?

Are they properly inflated?

I see you got some go fast goodies...how often do you use them?

If you are driving into head winds or up hills a lot...14.9 doesn't sound too awful, IMO.
Old 09-14-2008, 07:55 PM
  #3  
Registered User
 
rfeiller's Avatar
 
Join Date: May 2008
Location: San Jose, CA / Reno, NV
Posts: 318
Likes: 0
Received 0 Likes on 0 Posts
in city only driving in my cogested area i only get 10.4mpg 4.88's highway is 14.6 hand calculated. i keep reading these forums looking for that magic formula. some members are talking about 18-20+mpg don't believe they are hand calculating or do not have a factory stock truck.
both of the 03 & 05 5.9ctd dullys got about 4mpg more then the new 6.7 i have now. i realize i have a 5500, but without a bed it weighs about the same as the dullys, dodge boast about the increase in mileage so was disappointed in what i'm getting
Old 09-14-2008, 08:02 PM
  #4  
Registered User
 
mudder500's Avatar
 
Join Date: May 2007
Location: shreveport la
Posts: 603
Likes: 0
Received 0 Likes on 0 Posts
best i have ever gotten was 17.6 all highway at 68. In town i get 14.2 to 14.7.
Old 09-14-2008, 08:05 PM
  #5  
Registered User
 
glocklove's Avatar
 
Join Date: Jun 2008
Location: South West Fl
Posts: 405
Likes: 0
Received 0 Likes on 0 Posts
Actually I do hand calc. and my over head is off by 2 mpg. I filled up the other day and did my hand clac. came out to 16.87 mpg, my over head read 19.8 mpg. I drive in town 99% of the time, very little hwy miles. I have kept track of my milage since July of 2007. I calc out my average to date and it came out to 15.46 mpg. Thats 22 fill ups since July of 2007.
Old 09-14-2008, 08:16 PM
  #6  
Registered User
Thread Starter
 
cowboy2526's Avatar
 
Join Date: Jul 2008
Location: Godley, Texas
Posts: 182
Likes: 0
Received 0 Likes on 0 Posts
Yes the 07 is the one in question.

No I have not hand calculated it but i will to check for any difference.

I am running the stock size BFG all terrains

I have the smarty on all the time that is the only performance enhancing prodouct i have.
Old 09-14-2008, 08:38 PM
  #7  
Registered User
 
megacabdad's Avatar
 
Join Date: Jul 2008
Location: Erie, PA
Posts: 2,731
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by cowboy2526
Yes the 07 is the one in question.

No I have not hand calculated it but i will to check for any difference.

I am running the stock size BFG all terrains

I have the smarty on all the time that is the only performance enhancing prodouct i have.
Oh yeah...I saw Bullydog PMT...Now I see for gauges

Hand calc. is the only accurate way to get your MPG.

My overhead is off by at least 2 MPG's, and I've heard it gets worse with any electronics.

So hand calc. for a few tanks and see what you come up with.
Old 09-14-2008, 08:48 PM
  #8  
Banned
 
gus's 03's Avatar
 
Join Date: Sep 2005
Location: pacific north wet
Posts: 758
Likes: 0
Received 0 Likes on 0 Posts
that is low.
low 20's are average for me, average tank last's 750-775 before i fillit.
Old 09-14-2008, 09:03 PM
  #9  
Registered User
Thread Starter
 
cowboy2526's Avatar
 
Join Date: Jul 2008
Location: Godley, Texas
Posts: 182
Likes: 0
Received 0 Likes on 0 Posts
Wow that's alot.

What is the best way to hand calculate my mpg's
Old 09-14-2008, 09:29 PM
  #10  
Registered User
 
Danderson's Avatar
 
Join Date: Jan 2006
Location: San Diego
Posts: 3,443
Received 39 Likes on 31 Posts
Bunk mileage.

Driving like a granny,I only get 13 hand calculated with Smarty on sw# 1. I've got 285's@ 65psi ,G-56 and 2000# popup on my back. Only 9300 miles,so hopefully it'll get better. I'm going to leave Smarty off for a tank and check it again. I adjust for tire size with my GPS.
Old 09-14-2008, 09:35 PM
  #11  
Registered User
 
megacabdad's Avatar
 
Join Date: Jul 2008
Location: Erie, PA
Posts: 2,731
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by cowboy2526
Wow that's alot.

What is the best way to hand calculate my mpg's
I save my receipts, mark down my mileage, and divide that by the number of gallons I have left in my tank at each refill.

I also try to fill it up to the neck everytime as well.

The overhead is also only an average...i.e. if you let it idle for an extended period of time, the reading is going to drop like crazy.

On the other hand...go down a large hill with your foot off the gas peddle, and watch it skyrocket.

That's the main reason for hand calc...it takes out most of these variables.
Old 09-14-2008, 09:38 PM
  #12  
Banned
 
Speed Shift's Avatar
 
Join Date: Oct 2006
Location: Corpus Christi, TX
Posts: 1,136
Likes: 0
Received 0 Likes on 0 Posts
I get about 15mpg. When I went to 285/70s I lost about 2mpg and my G56 dosnt help either.

Also at 15mpg hand calculated my fatcory mileage calculator says im getting 21mpg.
Old 09-14-2008, 10:01 PM
  #13  
Registered User
 
J-man's Avatar
 
Join Date: Sep 2007
Location: Western Colorado
Posts: 610
Likes: 0
Received 0 Likes on 0 Posts
fill the tank clear to the top each time, and clear the trip odo each time you fill up. then divide miles by gallons. my actual is always around 10 % less than the overhead.
Old 09-14-2008, 10:27 PM
  #14  
Registered User
 
jmccart's Avatar
 
Join Date: Oct 2006
Location: SoCal
Posts: 1,998
Likes: 0
Received 1 Like on 1 Post
I usually get 13-14's. Once I got over 17 on a long fwy trip. I drive w/the rev's a tad higher at shifts since the bigger turbo. I definitely can't drive 55.
Old 09-14-2008, 10:28 PM
  #15  
Registered User
 
Mocho's Avatar
 
Join Date: Jun 2008
Location: Edmonton, AB
Posts: 793
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by Armstrong Performance
I get about 15mpg. When I went to 285/70s I lost about 2mpg and my G56 dosnt help either.

Also at 15mpg hand calculated my fatcory mileage calculator says im getting 21mpg.
G56 doesn't help? A standard will get better mileage then a auto. I get 16 in the city or highway doesn't matter, but I drive at 75 MPH on the highway. I idle it a lot in town and still get 16 so I can't complain. In the winter it drops by quite a bit though. My 35" tires have barely droped my city mileage, maybe 1 MPG but the highway mileage has more then picked that up so I haven't seen any difference overall.


Quick Reply: How come I can only get 14.9 mpg



All times are GMT -5. The time now is 07:45 AM.