Be careful coming past Harrisburg, PA. There is a lot of construction on the approach to the bridge over the Susquehanna River and it continues for a few miles up the highway in both directions. After that, you approach the Carlisle area, where the PA Turnpike interchange is located. Because of the design, if one wanted to leave 81 and catch the turnpike, one has to leave 81 and travel about a mile on route 11 to get to the turnpike. LOTS of trucks entering and leaving the highway here, and it seems there have been a severe increase in the number of accidents in the area usually involving a car and a semi getting in a fight.
There is a Flying J just off 81 at route 11 and they have a free station for dumping the holding tanks.
Jerry in PA