2021 Kenworth T680 Rough idle, rough drive

Hello y’all.

I’ve been driving for about two months now and something new has come up with my truck. Last couple of days, it will idle really rough and burning a lot of fuel (gauge says 5 gal/hour at idle) for a few minutes. Then go back to 0.5 gal/hour idle. Then repeat the cycle. Then, when driving it’s been really rough (noise, vibrating, etc). Hard to judge the fuel consumption when driving. But both feel like it’s doing a re-gen almost (but it’s not; re-gen light does not come on).

I’m driving a 2021 Kenworth T680 and would be curious to know if any of you have experienced the same. Thanks!