Some trivia:
. Tim Allen revealed on a talk show that he wanted the finale of the show to set up the reveal that Wilson was a ghost.
. The producers once approached Hillary Clinton about guest starring on an episode of the show.
. Ashley Judd was originally cast as the Tool Girl, which was supposed to be a much bigger role (a college student majoring in psychology who acted as a stand-in for Jill on the Tool Time set), but she pulled out only days before the pilot was shot.
. Frances Fisher, then-girlfriend of Clint Eastwood, was originally cast as Jill and the pilot was filmed with her in the role. Frances was known as a dramatic actor and struggled with comedic acting and lacked chemistry with Tim Allen and the audience and would be replaced with Patricia Richardson.
. The episode "The Longest Day", where it's believed Randy might have cancer, almost didn't air, as ABC felt cancer was too serious or controversial of a topic to feature in a sitcom.
. Al was originally just a placeholder character for another named Glenn to be played by Stephen Tobolowsky. Tobolowsky was unavailable to shoot the pilot so Richard Karn was brought in as Al to be a fill in character. When Stephen Tobolowsky was still unavailable once the series was picked up Tim Allen urged the producers to keep Karn on as he liked the way they worked together. They agreed and Tobolowsky was let go and Karn was kept on permanently.
. A very special episode about drunk driving was planned, but then Tim Allen got arrested for DUI and it was scrapped out of fear of being seen as hypocritical.