They are available 24/7 to help keep residents moving during the colder months.
The 39 state-of-the art gritting vehicles use 10,000 tonnes of salt stored at four depots.
Winter arrangements typically begin in October and run until the end of March although this period can be extended.
Snow has fallen in parts of Scotland after the coldest night of the winter so far.
The Met Office says freezing temperatures, ice and more snow are predicted over the next few days.
Temperatures could drop to minus 2 degrees in London on Friday, and minus 7 further north.
