I only use non-hydrogenated veggie oil when I filter or in my car. In short, hydrogenated oil is not commonly called veggie oil, but veggie shortening or veggie lard (ie. Crisco).
My pumping hot hydrogen gas under pressure and in the presence of a catalyst - veggie oil will cease being liquid at room temperature. This is what McDonald's and KFC use for cooking. This is also how margarine is made. Still think it's healthy?
So when you collect veggie oil for your car - be sure to ask that it's in fact veggie oil and not veggie shortening. Then ask again - "is it liquid at room temperature?" - some people need that last bit of clarification.