Everton keeper Howard has opted to take a year-long break from international football in order to spend more time with his family.
Howard's decision came on the back of his outstanding performances in the World Cup in Brazil, which saw Jurgen Klinsmann's side progress to the round of 16 before being knocked out by Belgium after extra-time.
Guzan is set to face Czech Republic in a friendly on Friday and the 29-year-old is eager to take his chance if Klinsmann gives him the nod to start in Prague.
"Hopefully I'll play in the game," Guzan told the Birmingham Mail.
"I had some brief conversations with Jurgen Klinsmann before we left Brazil and he's said it's now a new cycle.
"Everything from here, and backwards, it's all behind us now. It's all about 2018 now.
"We've got a busy four years as a national team."
Guzan admitted to having mixed emotions during the World Cup as he was restricted to sitting on the bench, but hopes his time will come.
"It's a tricky situation because you want to play," Guzan added.
"But, as I've always said, as a goalkeeper you are part of this union. There's an understanding that only one of you is going to play. Tim has been fantastic for the US.
"For me, when you're part of a World Cup team, it's no longer necessarily about who is playing.
"It’s all about helping the team and doing what you can to help the team.
"Whether you are playing or not it's about helping the team go further. We fell a bit short this time.
"But Tim has been over here for 10 or 12 years so if I have been consistent for two years he has been consistent for 10-12 years.
"You always want to be playing and in the team but for me when you are part of a World Cup team it is so much bigger than being an individual player. My job is to go week in, week out and try to get better and help Villa get results.
"To be in the American team and be part of a World Cup team was an honour and a privilege.
"The World Cup is the ultimate experience.
"I've been fortunate to be involved in two of them now. Hopefully, with a little bit of luck, come 2018 I'll be a part of a third and hopefully be playing."
