First view! Haven't had time to look it up yet, so can you say anything else please?
Synopsis - Bad sheriff hates army guys, Garner's son (Howell) gets arrested on trumped up charges and goes to county work farm. Garner has a Sherman Tank he refurbed as a hobby. Garner takes tank and busts son out of the pokey with the help of local prostitute. They run for the state border and make national news.
You figure it out from here.