Guus Bosman

"While the term Jake Brake technically only describes Jake Brake brand engine brakes, it has become a genericized trademark and is often used to refer to engine brakes or compression release engine brakes in general, especially on large vehicles or heavy equipment." Compression release engine brakes may make a loud chattering or machine gun noise while being used, which has led many communities to ban them. There are signs on the side of some freeway offramps, or at municipal boundaries, that will say "No jake braking", "Engine brakes restricted", etc. These signs are referring to compression release engine brakes.

(from http://en.wikipedia.org/wiki/Jake_brake).