How do you engage the 4wd in a 2004 ford f150 stx?

To engage the 4WD in a 2004 Ford F-150 STX, first come to a complete stop. Then, shift the transfer case lever located on the floor console to the desired 4WD mode (either 4H for high range or 4L for low range). Ensure the vehicle is in neutral when shifting into 4L. Finally, press the brake pedal and shift the transmission into gear to start driving.