They take on Grimsby this Saturday followed by Darlington and Mclean said: "Now that we know we have got promotion we can go into games and express ourselves.
"For myself and [Craig] Mackail-Smith, we still want to be scoring goals and giving the fans something to cheer about."
Mclean insists Posh will add to their achievements this season in the years to come.
"I'm sure the club will be eager to continue [their progress] and as long as I am part of this it is exactly what I want as well," he said.
"The summer will be interesting but I'm a Peterborough United player and as long as I am I will sweat blood for the club."