I have a 1994 chevy silverado with 5.7 tbi. Ac and heater do not blow at all. Cold and hot air come out of 5 he vents when going down highway. Can it be anything other than blower motor?

 

Can be the blower motor resistor, the fan switch, bad wires to and from the blower motor. Just have to get down there with a test light and test the wires at the blower motor. If the blower motor has power and ground at the blower connector, but the blower still doesn't spin, you have yourself a bad blower motor!