Back in 2006, original equipment manufacturers (OEMs) offered buyers the choice between an automatic and a manual transmission in 47 percent of new cars. Fast forward to 2018, when only 2 percent of vehicles sold had a manual transmission, according to edmunds.com.
The primary difference between DOT 3 and DOT 4 brake fluid is their respective boiling points. I suspect I know your next question. But first, some background. The U.S. Department of Transportation (DOT) classifies brake fluid into four main categories: