how my brain works

The other day I was stuck behind a cement truck driing down a windy road. After a while I noticed that it was actually turning, just really slowly, about two minutes per revolution. then, when I finally hit the interstate, still stuck behind it, it sped up to a more typical cement truck spin. Was it moving slowly because all of that weight spinning around would act like a gyroscope, keeping the truck from turning easily? Then, on the interstate, with wider turns, it wasn't as much of a big deal?