Thanks in advance for any idea on what's going on.

Within the past few months I have deleted my 2015.

I've got 5" exhaust w/o a muffler and running a raceme tuner.

I have tuned the transmission to a stock tune.

My question is that every time I slow to a stop the truck vibrates pretty bad.

I have figured out if after I stop I put it neutral and back in drive and the vibration stops.

While driving I dont seem to have any issues with it.

Any ideas what it could be?