On the F-450 I'm currently using the safety switch is on the e-brake, when you let the brake off with the boom on the truck dies. When we need to we push the e-brake in about 3/16 of the way, that way the truck will let the engine and the boom stay on and there is just enogh drag on the drive train so it will roll real smooth.
Never argue with an idiot, they will drag you down to their level and beat you with experience. Winston Churchill
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