While there are so many things that Ford did right when building the 2015 Transit, one strange aspect was they did not include nor produce a cabin air filter. There is a cabin air filter compartment behind the glove box, you will just need to buy this component from a third party.
A cabin air filter prevents dust, pollen and other pollutants from entering the vehicle through the heating and AC vents.
Tools / Hardware:
First press down on the two tabs in the back of the glove compartment to access the air filter compartment.
Once you have accessed the filter compartment and removed the filter cover, insert the Baldwin PA30000 filter with the air flow arrows facing down and angled corner facing the drivers side of the vehicle.
With the cabin air filter properly installed, simply replace the air filter cover and place the glove box into the proper position.
A very simple, quick and cheap way to keep the air in your van clean and your allergies at bay!