He replaced Jim Varney as the voice of Slinky Dog in Toy Story 3 and appeared as a biker in the film Bedtime Stories. He also had a recurring role on the Disney-produced sitcom Boy Meets World from seasons 2 to 7 as Chet Hunter, the father of Shawn Hunter (played by Rider Strong). He also played Farmer Fern in The Waterboy. Clark portrayed Uncle Mel in Good Luck Charlie.
Clark was born and raised in Macon, Georgia on February 2, 1946. He graduated from LaGrange College in 1969 with a degree in the performing arts.
- He was really good friends with Jim Varney in real life and in an interview for Toy Story 3, he described Varney as a very good friend and man.