Sunoco at 4 E. Mountain Avenue in Williamsport, PA is proud to partner with Weis Gas Rewards to bring you premium fuel choices and great savings. Enjoy regular, mid-grade, and premium Top Tier™ gasoline – all while earning Weis Gas Rewards every time you fill up. Inside the convenience store, pick up snacks, drinks, and daily essentials in a quick, clean, and welcoming environment.