If done correctley , a two tank wvo system will not hurt ur engine. I have aprox 60,000 miles on wvo and zero fuel related issues. If done wrong yes it can kill ur engine. I recentley just had my head off because of blown head gasket (non wvo related) and the pistions, cylinder walls, valves looked great. no issues.

Also i can run wvo in below zero temps, which u could not do with a 1 tank system running high concentrations of bio diesel or a 1 tank wvo system.

bio diesel may be easier in the beginning as far as vehicle mods go, but i think you will save more money in the long run because u don't have to blend it with diesel or pay for the supplies to make bio. All i spend money on is a few filters, that it

I have gotten 2500 miles to one tank of diesel fuel (15 gallons) in the summer. Obviousley i went thru many tanks of oil. I drive a substancial distance to work every day though.

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2005 e320 cdi (132,000)
2005 Jeep CRD diesel--2.8L (138,000 miles) wrecked, insurance took
1993 Mercedes benz 300D 2.5 Turbo Frybrid powered. (336,000 miles) wrecked and sold as parts car
1990 Mercedes benz 300D 2.5 Turbo (170,000 miles) wrecked and sold as parts car

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