Clean Idle Engines

The California Air Resources Board (ARB) requires that 2008 and later model year vehicles equipped with engines having tamper - resistant software which limits the time which the engine can idle speeds above low idle rpm). speeds above low idle, and without a O engaged, idle time will limited five minutes, after which the engine will revert back low idle. V ehicles equipped with a Clean Idle engine are identified a label which fixed the lower portion the driver ’ s side door cab - over models (MRU). W2056289 https://www.truck-manuals.net/mack/

The MERIT carrier assembly serial number located the left side the forward carrier , and the top the rear carrier