My goal is to eventually own a late model sprinter, Never thought of putting a Direct drive in one, although that's what ive done with almost every van/truck ive owned.
Running 100% WVO is more workable when the truck runs constantly while working, never letting the fuel cool down, especially in colder weather.
It is true that running your sole source of income on a friggen cooking oil is insane, due to possible down time etc etc... but I was insane/poor enough 5 years ago to jump in to it head first... understandably making MANY MANY MANY stupid mistakes along the way.
As of the last 3.5 years we have not had one minute of down time due to our use of 100% cooking oil,
Its all about how "Used up" the oil is (My oil I get is used from 11Am to 11PM then thrown out)
My first oil source used it for 3 FOOKIN WEEKS before they discarded it!!! it was like GRAVY.
Then its all about allowing it to settle in barrels, and pre-filtering.
After that its finding a way to heat up an axillary tank that holds the WVO (Easy peasy when you already have heated coolant lines running in a direct drive van)
And a way to switch from diesel to wvo and allow it to "Purge" the oil out of the system so you can shut down the truck.
My current cost per gallon of WVO after I have filtered it etc, is .10cents
And I buy 20$/month of diesel to purge the system every day after work.
Or you can spend 2k on a bio-diesel processor, and buy methanol and lye, and spend about $1.40/gallon to make your own fuel...
and still have to mix in 20/30% diesel to keep it from gelling in the winter.