I figured the problem was the drive belt so I ordered a new one. The simplest way to replace the belt is as follows (which took me hours to figure out). There were no instructions to follow until I realized I could ask on this web site. The instruction provided helped but was brief, so here is a detailed plan for you to finish in less than 30 minutes.
Unplug the dryer. At the bottom-front of the dryer, release the lower front panel by removing the bolt next to each of the two support legs with a 5/16" socket.
Open the door and under the upper lip are four screws. Use a star tool to remove. Now swing open the top of the dryer which then rests on it''s two rear hinges. Look down inside the front panel to find on either side two bolts holding the front assembly in place. Remove with 5/16" socket.
Carefully pull away the front panel taking care to remove the friction-fit door switch sensor wires. Under the left side of the dryer as you face it from the front is a spring loaded pulley pushing on the drive belt. Remove the belt from the pulley. With tension released from the belt, slip the belt off the motor and lifting the dryer drum a little, slip the belt off the drum and out of the dryer.
Dust on the drum may induce slipping of the drive belt. Remove all dust from the dryer drum using window cleaner and paper towel. Do not use soapy liquid or the belt will slip. Wipe what you can get to easily from the open top, then hand rotate the drum 90 degrees at a time to clean each section of the drum until all the dust is removed.
Put the new belt in place lifting the drum a little to slide over the drum. Re-engage the spring loaded tension pulley.
Replace front panel in reverse order. Make sure to reconnect the door-switch wires.