1999 monte carlo ls engine stutter

Hello, i have a 1999 monte carlo 3.1 with 112k on it. I havnt owned this vehicle for long, but what i have noticed is that when i am just cruising between 35-45 mph, the engine seems to stutter at around 2300rpm, or as if the transmission is confused to know when to lock in the engine and to let it slip. It doesnt seem to happen in 1st and 2nd gear, only in 3rd and 4th, and using over drive vs non-over drive doesnt make a difference. Is this a common problem on these vehicles? or could my tranny/ engine be taking a poo? Please let me know if you have any idea, thanks!

Welcome to AF, many things can cause this, without driving it it is nearly impossible make make a meaningful suggestion. Engine misfire, bad sensor, trans issues?