the stock air boxes on 99 and up silverados will out flow the stock throttle body which will allow up to like 450-500 horsepower. the box doesn't need replacin, it's the restrictive tube. look at the tube and you see the big air pockets that are on em. they let air flow in there to "reduce noise" but it also disrupts air flow. with a straight tube you get all the air. AirAid MIT kit is all you need. should be just the intake tube and a filter. if you're expectin to get the 15+ HP that's advertised then you'll be disappointed. but its your truck not mine.

I had a volant CAI and switched back toy stock box, k&n drop in filter, with the airaid tube and sold my brother the volant CAI, my mpg went up 1.5 mpg over the volant intake and it runs much better

 

I have the K&N CAI on my 6.0 liter. Any more power....un-noticable. Any more MPG....un-noticable. Any more performance...un-noticable. Any more sound....you can definetly here it sucking air under the hood when you apply medium to heavy throttle. It also changed the sound of my stock exhaust, it sounds more aggressive. Was it worth the $228.26 I paid for it?....not as a stand alone mod but with aftermarket exhaust maybe. Total install time was about 1 hour with common hand tools.

 

Wow! Such a huge amount of replies & opinions here. Time to re-consider my options, I suppose.

Thanks again!!

 

Ditto. I was looking to do something with my 07 6.0L LTZ suburban. Thanks for the info.

 

Hello,
I have the stock system in my 2010 silverado, if use the napa gold filter and i have the tube from a volant CAI will that work better than the OEM tube.

 

Any knowledge about possible issues with a KN filter. Read a post once that because they contain cotton fibers and debris they give off can screw up the sensors (wires) in the throttle body. When I first bought my 96 Silverado with 5.7 had to replace the throttle body. It came with a KN drop in filter for the stock air box. I removed the KN and have been using stock air filters. Truck sat for a year due to finances but now I am getting it back on the road and would like to know if I can use the KN. Thanks

 

It is over oiling of the K&N that cause the wires in the TB to screw up.

Just use the NAPA Gold (Wix) it filters better and performance is on par for the K&N with no oil.