Soybean oil is one of the more common vegetable oils.
When made into BD it tends to gel a few degrees higher than canola oil and some others.

It will burn just like any other VO.

What you are proposing is blending VO and #2, that is risky at best. If you want to run VO then convert your truck. If you don't want to convert your truck then learn to make BioDiesel.

Blending can cost you an engine.