How often do you clean/replace the exhaust filter and where is it?

The best source is the owner's manual. If you're speaking about the particulate filter, It may be scheduled as regular maintenance at a high mileage. I don't have any significant information on the particulate filter on this vehicle. If you want to ask a specialist, here's a directory link for you: https://repairpal.com/chevrolet-repair-in-salisbury-maryland