Building A Diesel for Fuel Mileage - Technical Article - Dodge Cummins Diesel Forum
3rd Gen. Powertrain Discussion of components that are directly involved in the power production and all that is needed to get and keep the truck moving . Engine , Transmission Ect...NO ADVERTISING

 12Likes
Reply
 
LinkBack Thread Tools Display Modes
post #1 of 30 (permalink) Old 01-16-2020, 01:40 PM Thread Starter
Diesel Head
 
MDSWA's Avatar
 
Join Date: Oct 2017
Location: NE Washington
Posts: 1,315
Thanks: 46
Thanked 144 Times in 140 Posts
iTrader Score: 0 reviews
Building A Diesel for Fuel Mileage - Technical Article

Here's a link to an interesting article on how to mod a 3rd gen for better fuel mileage. Funny thing is, the recommendations are almost an exact match to the mods I made to my truck - minus the Stealth 64, I'm still running the stock HE351CW. I can attest to the mileage improvements. 19-21 mpg on the highways is pretty easy. Best measured was around 23 mpg - all hand calculated. Best MPG mods were Smarty JR and modifying my driving style. 63 MPH and around 1800 RPM seems to be the sweet spot. Before mods I was at 17 -19 MPG.

https://www.dieselpowerproducts.com/...-fuel-mileage/


05 Ram 3500, SLT Bighorn, SB QC, Dynamic Stage 3 48RE, triple disc, billet input, S&B CAI, FASS Titanium, Smarty Jr., New stock Bosch injectors, Edge CTS, Hushpower/Magnaflow 4 inch, FTE Resonator, Bilstein 5100's, Redhead Steering, Truxedo, Linex

Last edited by MDSWA; 01-16-2020 at 06:43 PM.
MDSWA is offline  
Sponsored Links
Advertisement
 
post #2 of 30 (permalink) Old 01-16-2020, 06:44 PM Thread Starter
Diesel Head
 
MDSWA's Avatar
 
Join Date: Oct 2017
Location: NE Washington
Posts: 1,315
Thanks: 46
Thanked 144 Times in 140 Posts
iTrader Score: 0 reviews
Just fixed the link to the article - should be working now.

05 Ram 3500, SLT Bighorn, SB QC, Dynamic Stage 3 48RE, triple disc, billet input, S&B CAI, FASS Titanium, Smarty Jr., New stock Bosch injectors, Edge CTS, Hushpower/Magnaflow 4 inch, FTE Resonator, Bilstein 5100's, Redhead Steering, Truxedo, Linex
MDSWA is offline  
post #3 of 30 (permalink) Old 01-16-2020, 07:06 PM
Newbie
 
gearheadgregg's Avatar
 
Join Date: Sep 2019
Posts: 33
Thanks: 4
Thanked 5 Times in 5 Posts
Garage
iTrader Score: 0 reviews
My 2006 SLT LB (2 wd ) was by far the best Cummins i have had to date for fuel economy and my first purchased new .2 wheel drive makes a huge difference in MPG. After 50K miles and broke in my average was 25-27 mpg 13-14 pulling 9000K Toy hauler, I had to get a 4X4 for the climate i moved too , Looking at the Free-Spin Front locking hub conversion , Lots of moving parts and weight spinning needlessly, Should help with front steering and wondering on the road as they seam to do,, From what i have read around 2-3 mpg gain

2006 SLT 5.9 LB 2wd- 2007 SLT 5.9 4x4-2009 Big Horn 6.7 4x4- 2013 Tradesman 4x4 6.7
gearheadgregg is offline  
Sponsored Links
Advertisement
 
post #4 of 30 (permalink) Old 01-16-2020, 08:36 PM
TECH SPECIALIST
 
steve05ram360's Avatar
 
Join Date: Jun 2006
Posts: 10,877
Thanks: 560
Thanked 1,440 Times in 1,059 Posts
iTrader Score: 3 reviews
increasing the temptation to do a CAI tune using the afe stage 2 kit and see what max mpg could be. talking with a longt time tuning enthusist, he concurs with my position of hot air for mpg, cool dense air for power...

oh, and i still have the unopened s&b kit to play with.
steelhead1 likes this.

AFE PG7 drop in filter, AFE Torque Tube, HTT 2.5 turbo, AFE e-mani, ATS Arc Flo, 50HP DDP , 430k, HPTuners, G56, 25.065 mpg, mpg threads ->https://www.cumminsforum.com/forum/3...l#post23312562
steve05ram360 is offline  
post #5 of 30 (permalink) Old 01-17-2020, 10:32 AM
Diesel Head
 
Grogg's Avatar
 
Join Date: Oct 2012
Location: Ontario, Canada
Posts: 1,637
Thanks: 484
Thanked 238 Times in 206 Posts
Garage
iTrader Score: 1 reviews
Quote:
Originally Posted by gearheadgregg View Post
Looking at the Free-Spin Front locking hub conversion , Lots of moving parts and weight spinning needlessly, Should help with front steering and wondering on the road as they seam to do,, From what i have read around 2-3 mpg gain
nowhere near that much gain in MPG, real world varies from no difference to 0.5 MPG (basically margin of error)
gearheadgregg likes this.

2006 RAM 3500 DRW 6 speed 4WD QCLB: unit bearing delete, metric delete, all tow no go.
1991 W350 SRW auto 4WD RCLB: Fleetjunk delete, Garmon trans, NASTRUCK
Just say no to metric Daimler-Fiat
Grogg is offline  
post #6 of 30 (permalink) Old 01-17-2020, 10:42 AM
Diesel Head
 
Join Date: Jun 2016
Posts: 1,217
Thanks: 53
Thanked 161 Times in 147 Posts
iTrader Score: 0 reviews
Good article except for the FASS comments.
NEVER seen a fuel economy improvement in these below 500 hp putting on a $1000 fuel pump.

Shame American auto industry never put the money into American iron diesel car industry. Too much cheap gas for last century.
4BT turbo'd in a Dodge Dart streamlined body with 6 speed auto and an ECU tuned for fuel economy. ECU locked into 1800 rpms continuous with transmission speed control. Only drops to idle after 1 minute setting or downhill.

Or small constant rpm diesel driving high efficiency alternator>electric motor wheel drive.

Americans would NEVER stand for or buy a vehicle with little to no direct control of the throttle rpms and speed.
It's coming for public roads.

Fuel economy is 99% driver controlled.
tryNto likes this.
steelhead1 is offline  
post #7 of 30 (permalink) Old 01-17-2020, 11:24 AM
Diesel Head
 
Danderson's Avatar
 
Join Date: Feb 2007
Location: San Diego
Posts: 9,942
Thanks: 474
Thanked 967 Times in 864 Posts
iTrader Score: 1 reviews
Quote:
Originally Posted by Grogg View Post
nowhere near that much gain in MPG, real world varies from no difference to 0.5 MPG (basically margin of error)
It defies logic but I didn't see much of any gain in mpg with the hubs.
I'm returning to 285's when my 35's die. Between the popup Northstar,35's and the low final drive of my early G-56 mileage is pretty lousy. I've got the modified stock box,stock bumper,EFI and exercise restraint on the gas peddle. Some Dura Grappler's might be in the future.

'07 2500 SLT,5.9,Regcab.,G-56,4wd,Northstar TC800 popup 24/7. SBC OKHD. Dynatrac freespins and bj's. Synergy HD steering. Suspension mutt courtesy of Kore, Carli and Thuren.
Danderson is offline  
post #8 of 30 (permalink) Old 01-17-2020, 12:19 PM
TECH SPECIALIST
 
steve05ram360's Avatar
 
Join Date: Jun 2006
Posts: 10,877
Thanks: 560
Thanked 1,440 Times in 1,059 Posts
iTrader Score: 3 reviews
Quote:
Originally Posted by gearheadgregg View Post
My 2006 SLT LB (2 wd ) was by far the best Cummins i have had to date for fuel economy and my first purchased new .2 wheel drive makes a huge difference in MPG. After 50K miles and broke in my average was 25-27 mpg 13-14 pulling 9000K Toy hauler, I had to get a 4X4 for the climate i moved too , Looking at the Free-Spin Front locking hub conversion , Lots of moving parts and weight spinning needlessly, Should help with front steering and wondering on the road as they seam to do,, From what i have read around 2-3 mpg gain
Quote:
Originally Posted by Grogg View Post
nowhere near that much gain in MPG, real world varies from no difference to 0.5 MPG (basically margin of error)
Agreed... its not that much. I did back to back 126 mi runs in Minn in the winter and saw a 0.8 mpg difference. (cold weather mpg thread has that info in it)

Steering feel however is very noticeable.
gearheadgregg likes this.

AFE PG7 drop in filter, AFE Torque Tube, HTT 2.5 turbo, AFE e-mani, ATS Arc Flo, 50HP DDP , 430k, HPTuners, G56, 25.065 mpg, mpg threads ->https://www.cumminsforum.com/forum/3...l#post23312562
steve05ram360 is offline  
post #9 of 30 (permalink) Old 01-19-2020, 07:27 PM
Newbie
 
Ydnar's Avatar
 
Join Date: Dec 2011
Location: Conroe, Texas
Posts: 5
Thanks: 0
Thanked 0 Times in 0 Posts
iTrader Score: 0 reviews
I had an 05 3500 quad cab long bed 4x4 with 6 speed and the FASS, tuner, and cold air intake. That didn't really do much for fuel economy. She averaged around 15 all around. I now have an 07 2500 megacab 4x4 and she is heavy, close to 8000 pounds. Fab4's front and rear bumpers, 12k winch, flipbak bed cover, and gear behind the seat and in the storage area of that megacab. I've done a few mods, the Edge CTS, cold air, recent boost elbow and gen2 manifold swap, always been deleted with 5" inch pipe and an MBRB muffler. Overall she's mid 16's. On the hwy I can get close to 18. The difference is how fast I drive and how I let her shift. Stupid 48re loves to hang between gears on a gentle throttle. And with the 285/65r20 Michelin's OD doesn't kick in until 52-53mph. But running 67-68 on the hwy she only runs about 1680 rpm. It's when I run 70+ and start pushing 1860+ that the forces of wind resistance against that flat front end really takes its toll. I will say, when I first got her in Jun 2015, mpg was worse. The single modification to make the biggest mpg improvement was rebuilding the front end and getting her running straight as an arrow. New ball joints, hubs, Carli track bar, tie rod ends and drag link, shocks, and borgeson gear box and my tires have zero feathering. I align the tires myself with a simple tape measure, zero toe. Before all that, the additional drag of fighting loose steering and constantly fluctuating alignment had my mpgs in the low 14's.
Attached Thumbnails
Click image for larger version

Name:	Screenshot_20200119-174159_Fuelio_1579477408756.jpg
Views:	23
Size:	308.1 KB
ID:	865501   Click image for larger version

Name:	20191229_125654_1579477432742.jpg
Views:	17
Size:	305.7 KB
ID:	865503  

2007 2500 MegaCab 4x4 5.9 w/ 2nd gen swap, CTS2, train horn, auto leveling rear air bags, Fab4 front and rear, 12k winch, Carli track bar, total steering/ suspension rebuild,
so @172k miles she drives better than new.
Ydnar is offline  
post #10 of 30 (permalink) Old 01-20-2020, 11:44 AM
Diesel Head
 
Grogg's Avatar
 
Join Date: Oct 2012
Location: Ontario, Canada
Posts: 1,637
Thanks: 484
Thanked 238 Times in 206 Posts
Garage
iTrader Score: 1 reviews
here just to add some data about the free spin mileage thing from my 2006:

lifetime average before free-spin kit: 14.998 mpg over 69 tanks
average of the next 69 tanks with free-spin: 15.433 mpg
lifetime average after free-spin kit: 15.232 mpg over 146 tanks

other interesting stats:

lifetime average mpg: 15.157 mpg over 215 tanks
worst tank: 11.414 mpg
best tank: 19.425 mpg
number of aerodynamic mods: -4
extra tires: 2
steve05ram360 likes this.

2006 RAM 3500 DRW 6 speed 4WD QCLB: unit bearing delete, metric delete, all tow no go.
1991 W350 SRW auto 4WD RCLB: Fleetjunk delete, Garmon trans, NASTRUCK
Just say no to metric Daimler-Fiat
Grogg is offline  
post #11 of 30 (permalink) Old 01-20-2020, 11:55 AM
TECH SPECIALIST
 
steve05ram360's Avatar
 
Join Date: Jun 2006
Posts: 10,877
Thanks: 560
Thanked 1,440 Times in 1,059 Posts
iTrader Score: 3 reviews
Quote:
Originally Posted by Grogg View Post
here just to add some data about the free spin mileage thing from my 2006:

lifetime average before free-spin kit: 14.998 mpg over 69 tanks
average of the next 69 tanks with free-spin: 15.433 mpg
lifetime average after free-spin kit: 15.232 mpg over 146 tanks

other interesting stats:

lifetime average mpg: 15.157 mpg over 215 tanks
worst tank: 11.414 mpg
best tank: 19.425 mpg
number of aerodynamic mods: -4
extra tires: 2

Thats awesome! My GF was shooting for 12 mpg (downward)in her 2010 wrangler, big heavy tires, typical aero jeep. She reported earlier this week that she managed 10! High 5's all around hahaha. Needless to say, it rarely leaves the 10 mi radius of her house lol

AFE PG7 drop in filter, AFE Torque Tube, HTT 2.5 turbo, AFE e-mani, ATS Arc Flo, 50HP DDP , 430k, HPTuners, G56, 25.065 mpg, mpg threads ->https://www.cumminsforum.com/forum/3...l#post23312562
steve05ram360 is offline  
The Following User Says Thank You to steve05ram360 For This Useful Post:
Grogg (01-20-2020)
post #12 of 30 (permalink) Old 01-20-2020, 11:58 AM
Diesel Head
 
ofelas.5z's Avatar
 
Join Date: Feb 2015
Posts: 2,173
Thanks: 1
Thanked 239 Times in 214 Posts
iTrader Score: 2 reviews
Grogg.5z - your aero mods? https://www.cumminsforum.com/forum/o...l#post29205077

R12 in the summer, Webasto in the winter; cassette tapes & SAE-20078 all year.
ofelas.5z is offline  
The Following User Says Thank You to ofelas.5z For This Useful Post:
Grogg (01-20-2020)
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Dodge Cummins Diesel Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome