"What does B mean on Prius?engine brakingThe ""B"" creates something called ""engine braking,"" which mimics the behavior of a traditional transmission: It fakes a downshift to slow the Prius if it's descending a hill. ... To keep the brakes from being overloaded if you're on a long, steep grade.May 6, 2016Toyota Prius Mystery B Shfiter - Business - Insider"

"What does B mean on Prius?engine brakingThe ""B"" creates something called ""engine braking,"" which mimics the behavior of a traditional transmission: It fakes a downshift to slow the Prius if it's descending a hill. ... To keep the brakes from being overloaded if you're on a long, steep grade.May 6, 2016Toyota Prius Mystery B Shfiter - Business - Insider"