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Air filter question

1355 Views 15 Replies 7 Participants Last post by  AH64ID
I just bought my first diesel an 04 5.9 and I'm loving it. The truck came with no air box with a big k&n filter. Do You guys recommend this set up? It sound amazing with the 5" exhaust but I want to be sure I don't hurt my motor.
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If you have the stock filter/box, put it on.
I do not have the stock box but I could probably find one. What filter would be best with stock box?
Unless you are over 450-500hp run the stock box with the stock filter, and a Home Depot CAI.

check the turbo for excessive dirt when you pull the air I take, k&n's can be very hard on turbos.
I do not have the stock box but I could probably find one. What filter would be best with stock box?
Mopar 4" pleat filter.


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I have a K&N cone filter that fits the stock box and have cut the bottom out of the box. My intake tubes and turbo have always stayed clean. Been that way 100k now.
I have a K&N cone filter that fits the stock box and have cut the bottom out of the box. My intake tubes and turbo have always stayed clean. Been that way 100k now.
Your one of the lucky few, they have the worst rap of any filter for a reason.
What makes the k&n come filter with no air box get such a bad name? Does it not filter as well as having a box or k&n products are just crap?
K&n is basically just crap. But the biggest problem is oiled filters in general, not just k&n. If they're not oiled exactly right you either let oil through or dirt through.


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K&n is basically just crap. But the biggest problem is oiled filters in general, not just k&n. If they're not oiled exactly right you either let oil through or dirt through.


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Even if they are oil properly you can hold them up to the light and see too much of it.
I have a K&N in my factory box and I just ditched it for a napa gold 4" pleated filter when that filter goes b I will b changing the stock intake since I will b doing the 2nd gen mani and 63 in the next few months
I have a K&N in my factory box and I just ditched it for a napa gold 4" pleated filter when that filter goes b I will b changing the stock intake since I will b doing the 2nd gen mani and 63 in the next few months
Good move on the 2nd gen swap :thumbsup:
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Since I bought my truck it hasn't had the stock filter. When I bought it. It had a afe stage 1. Now I have a 6"x12" s&b cone filter. I haven't had any dust or oil in my intake tube. Also on every cone filter I've ever owned, I have ran an outerwear over it.
Could someone explain the homedepot CAI??
Cold Air Intake (CAI) u drill a hole in the bottom of the air box and plumb in a piece of PVC into the box and run it to the bottom of the fog light area
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