Suarez was among a handful of drivers who bolted to the top of the leaderboard very late in the 50-minute session.
His average lap speed of 171.217 mph just topped Ryan Blaney (171.090 mph) and Alex Bowman (170.338 mph). Kyle Busch was fourth and Brad Keselowski completed the top-five.
Suarez finished a career-best second in last year’s second Pocono race, leading 29 laps in the event.
“It was pretty good. I’m pretty happy with the No. 41 Ford Mustang,” Suarez said after practice. “The guys have been doing a very good job. We were really quick.
“When you unload from the trailer quickest it’s always a little easier to go through practice. I think we need to be a little bit better in the longer runs but I felt like we will all work in the second practice to get better on the long runs.
“The most laps we ran were five or six laps. I guess second practice will be more racing-related. So, we’ll see what we have.”
Many teams seem to wait until late in the session to make mock qualifying runs. Qualifying this weekend at Pocono is Saturday morning before the Xfinity Series race.
Rounding out the top-10 in practice were Denny Hamlin, Joey Logano, William Byron, Clint Bowyer and last weekend’s race winner, Martin Truex Jr.
Rookie Matt Tifft sat out the final 15 minutes of practice after his car twice failed pre-race inspection last weekend at Charlotte.