Not surprisingly, it's also the most common email (and phone call) question that I get.
So, loyal readers, here are my top three choices for SVO trucks:
- 1994-1998.5 Dodge Cummins 5.9l 2nd gen 12 valve
- 1989-1993 Dodge Cummins 5.9l 1st gen 12 valve
- 1983-1994 Ford International 6.9/7.3l pre-Powerstroke
Now, here's the details:
Straight Vegetable Oil (SVO), even when heated, is still thicker than diesel. You need a truck with an injection pump than can withstand the added stress of SVO.
The strongest injection pump out there out there is the Bosch inline P7100, found on 2nd generation 12 valve Dodge Cummins trucks.
The best SVO truck:
1994-1998.5 Dodge Cummins 5.9l 2nd gen 12 valve
Other good candidates for a vegoil conversion are pre-Powerstroke 6.9/7.3 Fords with the regular Stanadyne injection pumps and 1st generation 12 valve Dodges with the Bosch VE rotary pump. Personally, I convert a lot of VWs with the Bosch VE pump, and have good luck with them, so I would prefer a Dodge, but they are harder to find than the Fords. In early 1994 Ford made a turbodiesel version of the 7.3 IDI, it's the newest, most powerful of the old-style pre-Powerstroke engines.
Common, easier to convert diesel trucks:
1989-1993 Dodge Cummins 5.9l 1st gen 12 valve
1983-1994 Ford 6.9/7.3l IDI
Halfway through 1994 Ford switched from an Indirect Injection (IDI) engine to a Direct Injection (DI) system with a Hydraulic Electronic Unit Injection (HEUI), a type of Common-Rail system, instead of a regular mechanical injection pump. These are very common, but the fuel routing issues cause purge times to be almost 15 minutes with a standard conversion. With the extra modifications to reduce purge times, these can run vegoil very well, but may cost $1000-$2000 more.
Common diesels that may require more complex, expensive conversions:
1994.5-1997 Ford Powerstroke 7.3l 1st gen
1999-2003 Ford Powerstroke 7.3l 2nd gen
GMC/Chevy trucks have a very sensitive injection pump that is known to break when running straight vegetable oil. I don't recommend converting these trucks, although there are a few local GMC fanatics who are running SVO.
The Dodge VP44 is a radial-piston rotary pump, instead of the axial-piston VE rotary pump, and that makes a lot of difference. Basically, the VP44 is a sensitive pump that breaks easily on straight vegetable oil.
1982-2000 GMC/Chevy 6.2/6.5l
1998.5-2002 Dodge Cummins 5.9l 24 valve
Yeah, but what about the newer trucks? Ummmmm, they're newer. All have Direct Injection (DI) engines with some sort of common-rail injection system, and would require at least as much additional modifications as the 7.3l Powerstrokes. We can convert them, but consider converting them experimental and expensive.
And what about Isuzu, Toyota, International, and other early 80's trucks? Well, most of them are pretty good candidates, but info on the rare trucks is beyond the scope of this piece, although I've happily driven an old VW pickup for years on SVO.