Help!!!

I just bought a 2004 Pontiac Grand Am with 110,000kms on it. It runs really well but I have noticed a problem. When I am holding steady at any speed (say 50kms/hr) the car seems to lightly chug. The rpms don't fluctuate (or so it seems), the car just seems like it's chugging slightly. It doesn't matter what speed I am cuising at, when its at a steady speed this happens. Acceleration seems fine. Any suggestions?

P.S: Sorry for the broad terminology here :) I'm trying to describe it the best I can. Thanks!!

Welcome to AF !

Have you ever had the trans fluid & filter changed ?

Could be nothing since the rpms dont change.
Though it is recommended you change your trans fluid & filter every 40-50k miles or in your case every 64-80k km.