disconnect the ECM wire connector. remove the bolts from the right side of the instrument cluster. pull the cluster out far enough to gain access to the bolts and remove the fan. I would get a replacement from a wrecker with the blades installed. If you get the blades off center they will make noise or cook the new motor prematurly.
There will be a rubber coated , moulded insulation cover on the motor. There will be a wire to disconnect on a tab connected to the motor housing. On the right side underneath the dash will be a forked bracket that will have a nut on it. Remove that nut and pry the dash off of the stud and pull forward about a half an inch. If you dont do that, the motor will not clear the bottom of the dash when you remove the motor. Remove the black screws that hold the motor housing and pull out the fan straight out and the tilt back. The above post is right. It is critical to mark the old motor exactly how it was found or it will rub. Do not drop or bang the new motor or it will rub. You can buy a replacement fan at auto zone.
Remove the wiring harness from the back of the blower motor in your 1993 GMC 1500. Remove the blower motor retaining bolts. If the new blower motor does not have the fan attached to and you will need to remove the fan from the old blower motor. Reverse the process to install the new blower motor.
Go To Your Underhood Fuse/Relay Center Located Near The Master Cylinder. You Will Find The Relay There.
On the passengers side, remove the glove box and door and its mounted to the top of the a/c heater box by two screws..............
Its a 5.7L 350 engine
usually mounted on or next to blower motor
If you are sure that everything is working correctly then check the ground going to the blower motor assembly.............. Which goes through the blower resistor.
blower motor for 1998 gmc sierra 4x4 is located on the passsenger side,under the dash, you will need to remove the glove compartment door for easier accessand to remove blower motor cover.
Look at the passenger side firewall Some are removed from the exterior Some are removed from inside behind the glove box
Under the dashboard at the feet of the passenger side.
Passenger side under the hood.
Under the dash on the passenger side.
The Chevy SBC 5.7L 350cid V8 was the standard