So what is the downside to turning it on and leaving it on? The unit works continuously preventing sticking, the unit works all the time reducing brake wear, the unit allows the driver more control by the throttle, the operator is more aware of what is happening with his vehicle? There are thousands of posts pertaining to this on the TDR, DTR, Cummins Forums, Ram Chat. Unless it becomes extremely slippery their is no good reason not to have the unit operating and unlike a "Jake Brake" on a big truck it WON'T kill your engine stopping the wheels completely. OEM vehicle manuals are generic information does not make them 100% correct for all situations.