wondering what normal idle rpm would be just purchased this truck1999 2500 4x4 Quad cab it is 900 rpm seems high to me dont know any one around me with one to compare I work on heavy trucks cummins isx cat c15 most idle at 600-700 rpm dont have alot of experiance with these b series only in a few buses . been wanting one finally got it love it so far. :-laf