12 Valve 2nd Gen Dodge Cummins 94-98 Discussion of 12 Valve 5.9 Liter Dodge Cummins Diesels with P7100 Injection Pumps

TERRIBLE mileage on my 5spd cummins!! 11mpg city!

Old Mar 19, 2010 | 10:35 PM
  #21  
Benjamin's Avatar
Bombardier
Joined: Mar 2007
Posts: 9,655
Likes: 607
From: Da' Dirty South
Default

i think it mainly depends on the area and the snap on guy. some guys sell by the book, some give discounts.....
 
Reply
Old Mar 19, 2010 | 10:44 PM
  #22  
Dr. Evil's Avatar
BOMBARDIER
Joined: Mar 2007
Posts: 23,293
Likes: 1,322
From: North of You
Default

Snapon/Mac prices vary - dont they?
 
Reply
Old Mar 20, 2010 | 05:52 PM
  #23  
85_305's Avatar
Thread Starter
|
Being Evaluated
Joined: Feb 2010
Posts: 1,905
Likes: 15
From: Buffalo, NY
Default

I would figure them to all be the same. I dont know. I'll ask my dad to ask the snapon guy though
 
Reply
Old Mar 21, 2010 | 10:46 AM
  #24  
wes-cummins's Avatar
Diesel Wrench
Joined: Dec 2009
Posts: 576
Likes: 10
From: wisconsin
Default

every snap on guy quotes a different price around here
 
Reply
Old Mar 21, 2010 | 06:24 PM
  #25  
TXHC's Avatar
Diesel Enthusiast
Joined: Jan 2009
Posts: 121
Likes: 19
From: Texas
Default

Update on my mileage from previous post. Was getting 23mpg with the new fuel filter & cleaned pre-filter/strainer. Installed the BHAF last Friday and on this tank I got 24.665mpg. Then I'll see what happens when the exhaust gets opened up.

85_305, have you checked the wastegate's operation? If the wastegate isn't operating correctly or the actuator is out of adjustment, the fuel mileage could be affected as well, but usually with low power as another symptom. Gauges would help...low boost and high EGT's would tell you something.
 
Reply
Old Mar 21, 2010 | 06:39 PM
  #26  
85_305's Avatar
Thread Starter
|
Being Evaluated
Joined: Feb 2010
Posts: 1,905
Likes: 15
From: Buffalo, NY
Default

Well I put a new starter in teh other day, and I also put in my fuel plate and afc work (see sig), new fuel filter, and straight piped my truck. Next mod is the bhaf (air filter in it now is dirrrrty.. its ragged) and boost elbow. I'll see how mileage is just with the new mods and report back, but be forewarned my first tank on the 'plate is getting ragged pretty good I cant believe how nasty this truck is with a 30$ plate, and the afc and plate aren't even full forward yet until I get the gauges. I cant wait to get my boost elbow and put the afc and plate ff though, talking about excitement!
 
Reply
Old Mar 21, 2010 | 06:42 PM
  #27  
bobcat67's Avatar
Diesel Bomber
Joined: Dec 2008
Posts: 1,222
Likes: 140
From: Bozeman, MT
Default

i get anywhere from 11 to 22mpg mostly depending on the go pedal position
 
Reply
Old Mar 21, 2010 | 06:51 PM
  #28  
85_305's Avatar
Thread Starter
|
Being Evaluated
Joined: Feb 2010
Posts: 1,905
Likes: 15
From: Buffalo, NY
Default

Comparing a common rail to a 12v is a bit outrageous, no?

But 22mpg all around or just city or what?
 
Reply
Old Mar 21, 2010 | 06:55 PM
  #29  
TXHC's Avatar
Diesel Enthusiast
Joined: Jan 2009
Posts: 121
Likes: 19
From: Texas
Default

Heh, it's hard to get good fuel mileage when you can't keep the -eatin grin off your face and the go-pedal on the floor! Those mods on your truck probably woke up a sleeping beast. I know when I had my '97 5-spd dually and did the fuel plate, exhaust, bhaf...i felt like I was driving a new truck and probably got about 10mpg for the first few tanks until the excitement wore off! Even after those mods, it still got 26mpg best, 22mpg avg, and 19mpg hooked. I loved that truck
 

Last edited by Benjamin; Mar 24, 2010 at 11:36 AM.
Reply
Old Mar 21, 2010 | 07:25 PM
  #30  
bobcat67's Avatar
Diesel Bomber
Joined: Dec 2008
Posts: 1,222
Likes: 140
From: Bozeman, MT
Default

yeah i'm sure comparing a common rail to 12v is a bit outrageous, and 22 is going downhill at 75mph for 150 miles running at 1700rpm, 3.73's and 40" tires makes for low cruising rpm's, but usually i get 17-18 on the interstate and 11-15 around town, i'm not gonna complain though, it's better than a gasser and alot more fun
 
Reply

Thread Tools
Search this Thread

All times are GMT -5. The time now is 05:10 PM.