[turbo6bar]

If I were in OK, I definitely would not get a compressor. Here in TN, however, stations are very rare.

If I depreciate the machine and conversion kits out over 5 years, it'd be just a little better than break even. After the 5 year mark, however, the cost savings are significant. It really depends on the durability of the compressor. Will it hold some value over time? Will a rebuild truly cost only $800? Will gasoline stay around $3.50/gallon? Unless hydraulic fracking is banned, I don't see natural gas prices going up dramatically.

If I could get my diesel on a natural gas/diesel mix, I'd be all in.

The compressor really is the stick in this equation.