I have always used DOT 3 brake fluid in my 47 Chevy with an original type brake system. Components were all replaced with new around 2008. I eventually noticed that the brake fluid bottle says "synthetic". Having asked Dr. Google about this, the recurring theme seems to indicate that since DOT 3, 4 and 5.1 (NOT DOT 5) are polyethylene glycol based, which is noted elsewhere to be a "synthesized" compound, the upshot appears to be that ALL DOT 3 is "synthetic". Further, the appearance of the word "synthetic" on the bottles in the last 15 or so years may just be a bit of labeling eye candy.
Looking for a knowledgeable source to weigh in on 2 questions: Is there such a thing as conventional vs synthetic DOT 3 brake fluid?
On a side note, I moved the question here from a facebook group, having gotten everything from irrelevant to just stupid responses. Lesson learned :-D
