Who played Grumpy old mans voice?

The voice of Grumpy Old Man, specifically the character of Grandpa Lou Pickles in the animated series "Rugrats," was voiced by actor and comedian Charles Adler. Additionally, in the movie "Grumpy Old Men," the characters John Gustafson and Max Goldman were played by Jack Lemmon and Walter Matthau, respectively. If you are referring to a specific character or context, please clarify for a more precise answer!