Hey Scotty, just bought my first truck for $15k, a 2012 Ford F-150 STX with the 5.0L V8 engine, only 77k mileage, personal use ... but has an aftermarket exhaust

I've seen a bunch of your videos any why switching out the stock muffler can be bad. Would I be able to determine if the new muffler put on is tuned properly with the engine, making sure things are programmed right and firing properly? 

In your videos you mentioned changing the muffler can cause different problems if the computer isn't reprogrammed/tuned to the new exhaust since you're affectively changing the airflow. 

If there's a way I can check this out to verify if changing the muffler back is a high priority or not. If I can determine that it is okay and doesn't need to be changed right away then I'm fine with keeping it for a bit.. I'm a young guy so a little notice ain't so bad. 

Because there were some other things I was hoping to get done first and foremost which was changing the oil, transmission fluid, battery (needs a new one), installing a backup camera, heck even switching on some silicon wiper blades, etc. those things I want to get done first just for me to know that I got this truck started off on the right foot here to keep her running like a dream. Previous owner just changed on new high quality brake pads which is nice. Truck is from upstate new york so there is some minor rust but nothing major, hoping to tend to that when the weather gets warmer.

So my biggest dilemma is determining the exhaust system if needs to be changed sooner or can wait. Thanks scotty