There are a few places on Route V with traffic. It's unavoidable. Clearfield and Du Bois are two places that come to mind. But it's generally not bad most of the way, and the stretches with heavier traffic are not long. It also depends on the day and time of day. For example, Clearfield is the county seat of Clearfield County, so the courthouse and other country offices are there. It's the main driver of the downtown economy. Outside of business hours and on the weekends, traffic drops considerably. Same for Bellefonte, which is the seat of Centre County. Route V goes right past the majestic courthouse where former PSU assistant coach Jerry Sandusky was tried.
From the photo after the trail to the pig shots are on Route V from Emlenton to just west of Catawissa:
I turned south from Catawissa to get home to Philly.