99 f 450 7.3 can start will not shift out of park
Might seem like a stupid response, but are you depressing the brake pedal before try to shift? Many vehicles have a brake/shifter/interlock. Also, if you have it parked on an incline (UP or down), it can be difficult to get it out of Park (takes more effort to get it out of Park). If you park on an incline, it's best to set the parking brake before you put the shifter in the Park position.
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