Generally, any sale at retail or use of a vehicle within this Commonwealth is subject to tax. This shall include the isolated sale or use of a vehicle required to be licensed or registered under either Federal or State law.
61 Pa. Code § 31.42
This section cited in 61 Pa. Code § 31.7 (relating to use tax); 61 Pa. Code § 31.41 (relating to definitions); 61 Pa. Code § 31.41a (relating to scope); 61 Pa. Code § 33.2 (relating to purchase price); and 61 Pa. Code § 60.16 (relating to Local Sales, Use and Hotel Occupancy Tax).