He played the voices of some characters from Don Bluth's films, such as Jeremy in The Secret of NIMH and its 1998 sequel, Stanley in A Troll in Central Park, Tiger from An American Tail, who was one of the voice actors throughout the franchise, and Itchy Itchiford from All Dogs Go to Heaven, who was one of the only two voice actors who made it through the whole franchise, the other being Charles Nelson Reilly as Killer. Additionally, he provided the voice of Christopher Columbus in The Magic Voyage and was also known for voicing Pizza the Hutt (a parody of Jabba the Hutt) in Mel Brooks' Spaceballs (a parody of Star Wars).
For Disney, he voiced Fagin in Oliver & Company and Dionysus in the Hercules TV series. He also hosted the Mouse Factory episode "The Great Outdoors". Additionally, he guest-starred on The Muppet Show. He was chosen to voice Ernie from The Brave Little Toaster; however, the character was cut from the film.
He died from kidney failure, cancer, and respiratory problems due to complications of diabetes and was cremated; his ashes were buried with his parents and is survived by his wife and three sons, including David.