An article series on converting a FORD F-250 to run dual fuel. The CNG helps lower the cost per mile for fuel. In [6] parts.
F250 Powerstroke Natural Gas Conversion Project Pt. 6 « The CNG Times
Given a good local cost for CNG (and lower than propane), one can considerably extend the range of diesel carried aboard.
In this and other articles it looks as though conversion costs are from $1500-$3000, the tanks being the highest portion of the cost.
A conversion calculator is included at this conversion companys website (linked page is for mobile turbodiesels, calc at page bottom):
C&E Clean Energy Solutions | Sturgis, South Dakota
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