Anyone know what this is?

So went looking for what "loud" muffler this Tundra had and didn't find one... Well that explains that... And then I saw this thing. Never seen one of these before (coming from the 4runner world) anyone know what this box is? CD changer plugged into the diff? Lol

 

Emissions stuff for gasoline vapor collection.

 

X2

 

Thanks Jim and Wynnded!

 

It's the evaporation / charcoal filter system for gasoline fumes.

 

Yep, everyone's spot on. I'll tell you though.. that thing looks cheap, but it's damn expensive to replace. Tip - when you fill up your gas tank, don't top off. Once it clicks stop... don't go for that extra 0.5+gallons. Apparently when you top off, you can end up having gas go to that evap /charcoal filter. Do it enough, your truck will throw an EVAP code. You'll end up searching for the problem... trying cheap solutions like replacing your gas cap, searching for vacuum leaks. Until you finally replace that filter.

Don't ask how I know...