 He declined an invitation to appear on "Late Show with David Letterman" despite speculation he would make an appearance on the show's finale.Leno has hosted an hour long "Jay Leno's Garage" special on CNBC, and the show has aired as a primetime series on the cable channel since 2015.Leno has also been a cast member of the Tim Allen comedy "Last Man Standing" since season 5 (2015).