first gear vs low gear

first gear

noun
  • The first gear of an transmission, which provides the lowest output speed and greatest mechanical advantage. 

low gear

noun
  • The lowest gear available from a gearbox, typically in a motor vehicle or cycle. 

  • One of the lower gears available from a gearbox, typically in a motor vehicle or cycle. 

How often have the words first gear and low gear occurred in a corpus of books? (source: Google Ngram Viewer )