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Old 12-26-2019, 09:37 AM   #18 (permalink)
Join Date: Oct 2009
Location: Fort Worth, Texas
Posts: 2,442

2004 CTD - '04 DODGE RAM 2500 SLT
Team Cummins
90 day: 19.36 mpg (US)
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1). Since the changes started for FE = Odometer Miles?

2). Engine Hours (looking for Average MPH over that span of miles as a change in Average MPH can account for all claimed MPG improvement).

3). Fuel cost (CPM; cents-per-mile; adjusted to a constant dollar figure per gallon).


A). Net income used to purchase supplies, gear, equipment for FE changes.

B). CPM adjusted accordingly (for, as a “fuel cost”, vehicle expense has increased)

It’s one thing to talk of improvements, but it’s only after their advantage has recouped cost that savings begin. (This would include those things removed)

Net income, is the thing. 12% reduction has meaning. In a 20,000-mile year at $3/gl it’s almost $500 in fuel (160-gals).

The real questions are:

I). What’s the CPM trend, in other words? Conjecture is that it hasn’t improved at all in spending-to-save (miles held constant).

II). Have e-fans (all changes) been put to the test? Towing greatest trailer frontal area and/or weight? Max axle loads with or without trailer? Otherwise need to add a note that truck has been de-rated to half-ton status regarding ability to do work.

Optimization of “empty” isn’t an FE goal for a pickup truck.

And I suggest you put the truck on a CAT Scale. My ‘04 2WD weighed more than 6800# when new. (CAT SCALE app. As the heaviest tire load per axle is the single accurate method of setting cold tire pressure it’s a necessary tool).


Last edited by slowmover; 12-26-2019 at 10:29 AM..
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