Unplug the dryer and move it as far away from the wall as you can so you can safely work on all sides of it.
Open the door and remove all the screws inside the opening. Carefully disengage the front panel and lift it off.
Check the dryer drum and the rubber belt that runs around it. You have a clear view of the drum and the belt once the front of the Frigidaire dryer is removed. Check the belt for any worn areas, dry spots or cracks. If the belt is badly worn, replace it. If the belt is in good shape, lubricate it to get rid of the squeaking noise.
Find the spot on the belt where it lifts away from the surface of the drum and makes its way through the pulleys that run the dryer motor. Use a piece of chalk to mark that spot on the drum.
Move the drum slowly with one hand while you spray a steady stream of belt dressing to the spot where the belt rises off the drum. Continue to turn the drum and spray the belt until you are back at the spot you marked with the chalk. Reassemble the dryer, put a load of clothes in and test the appliance for squeaks. Relubricate the belt if the dryer is still squeaking.