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!

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  #21  
Old 03-19-2010, 10:35 PM
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i think it mainly depends on the area and the snap on guy. some guys sell by the book, some give discounts.....
 
  #22  
Old 03-19-2010, 10:44 PM
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Snapon/Mac prices vary - dont they?
 
  #23  
Old 03-20-2010, 05:52 PM
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I would figure them to all be the same. I dont know. I'll ask my dad to ask the snapon guy though
 
  #24  
Old 03-21-2010, 10:46 AM
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every snap on guy quotes a different price around here
 
  #25  
Old 03-21-2010, 06:24 PM
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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.
 
  #26  
Old 03-21-2010, 06:39 PM
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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!
 
  #27  
Old 03-21-2010, 06:42 PM
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i get anywhere from 11 to 22mpg mostly depending on the go pedal position
 
  #28  
Old 03-21-2010, 06:51 PM
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Comparing a common rail to a 12v is a bit outrageous, no?

But 22mpg all around or just city or what?
 
  #29  
Old 03-21-2010, 06:55 PM
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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; 03-24-2010 at 11:36 AM.
  #30  
Old 03-21-2010, 07:25 PM
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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
 


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