I have herd that up grading the cold air intake can help with gas mileage. Is there any truth to that? If so what system should I up grade to?

 

This is false. They are useless unless your truck is properly tuned for one. Even still....virtually no benefit

 

The benefit is minimal if not nonexistent for the cost of a CAI setup. The OEM set up is already by definition a "cold air" intake. If you want to do anything at all, look into the Gotts Mod if you want to do anything regarding air intake. This will cost you about $20 at Lowes instead of $200+

 

Does nothing, 6 million threads about this

 

Even doing GOTTS/DWV won't give you much real world increase without some other additional modifications/a tune because the stock intake provides more than enough air for the engine (in real world tests, not just anecdotal).

 

Exactly this... Do a search, you will see.

 

I have a Roush CAI for 3 years now, I like it very much, very easy to remove and tons of room. Oh! and butt dyno is very happy.