We live in AZ but travel to PA at least once a yr. This is one of our favorite stops, especially during race season. Plenty of room for a big rig. Shuttle service to the Casino/Racetrack is continuous and convenient. Several others have mentioned the "Grass Strips". Be careful during wet/rainy weather as there are a few RVrs that are real scumbags and have dumped tanks in that grass. There is a TA, with a dump station ($), a few miles away, East on I-90.
Erie is a very historic town and has a lot to see and do. If you are there, when they are in the harbor, don't miss the "Tall Ships"