RedneckWithPaychecks
454/350 x (4x4)²
I had a 1999 CCLB 2wd 3500 without heat, full base model with no options at all. I don’t remember having a “heavy duty heater”, do you have the sliding controls or the “deluxe” style with buttons and a screen? If you have head vents then I think it’s ram air “conditioning” (I assume it’s conditioning for dealing with no A/C).