S2·E8 Hamhocks and Armlocks

Dexter's father gets challenged to an arm wrestling match against a local champion at a truck stop, when he causes the champion to lose for the first time, but refuses to do so even when he trashes the family car. He finally accepts the challenge when he slams the door in Mom's face. Dee Dee knows he'll get creamed, so Dexter builds him a robotic arm to help him win the match.