OK So I was told that I could just swap the Napa 6637 filter in place of the K&N that was on this truck when I bought it. I guess I should have measured because the intake tube steps down to a smaller diameter for the K&N. Here is a picture of what I have, I guess my question is what do I need to get the 6637 filter adapted to what I have? Do I need to find the stock intake tube and then add the small 4" kicker to the end or is there something else out there? Sorry its hard to tell from the picture but you can see the red boot and then the piece of tubing coming from there to the filter.

 

Your pic doesn't show the filter or the rest of the tubing. It looks like it's using a piece of exhaust pipe. You probably just need a piece of 4" exhaut pipe with a 45-degree bend, and no turndown.

 

Yeah sorry I thought I had a better picture on my phone. I'm thinking this would work but I need to take some measurments I guess.

 

WAG - that ^^^^ should work, athough it's a bit spendy.

 

Check with a local exhaust shop before you buy that. I'd bet you could get it cheaper and faster.

 

Yeah I was thinking the same thing. This one is a bit cheaper and I guess I could cut to length.

 

Still more expensive than cheapo exhaust pipe. But the polished aluminum will look nice and hold up, and you've got LOTS of leeway at either end for a custom length cut.