Air cleaner after filter

My name is Phil. I just took possession of this vehicle and it is a one owner with 250K miles on it and runs like a dream. I have a question regarding the stock air cleaner after filter. It looks like it was never meant to be removed or replaced. Seems like overkill to me. I'm a believer in the stock design, but I can see what color(nice and white) it was when new and now it is black. I have every reason to believe it had regular maintenance since I know the previous owner. What does the Tundra community think about this. Also, I need a service manual and can get one at the automotive parts store, but would also like to know what y'alls opinion is on the most trusted source of service manual(probably on disc at this point) would be. Thanks for your consideration!
Phil

 

You probably mean the carbon filter inside the box lid? It’s not really a filter as much as it is meant to absorb the fuel vapors when your truck is turned off. Vapors from inside the intake work their way out, this is meant to absorb them. More of an emissions thing. I removed mine LOL

 

Nuff said, Mr. Blonde! I'll leave it just the way it is. I'd bet that is the first thing to go if you are looking to boost performance. I'm really quite shocked at how thirsty this engine is, but it is hauling a lot of four wheel beef around. Thanks for the info!
Phil

 

I removed mine too. No idea if it did anything, but it's low hanging fruit on the way to a better flowing air compressor.

 

What year model???

 

Theres a charcoal filter in the intake? And for routine service a Haynes or Chiltons will work fine. It's what I have.