6637
Post Fiend
Joined: Mar 2007
Posts: 26,966
Likes: 50
From: Texas
The 6637 is a filter commonly used on the 7.3 engine. It's a rather large filter that has a good filtration rating.
Pete's cover is a cloth pre-filter that slips on top of the filter to extend the life of the filter, and some like to customize it to make it look better.
Photo Gallery
Pete's cover is a cloth pre-filter that slips on top of the filter to extend the life of the filter, and some like to customize it to make it look better.
Photo Gallery
Senior User
Joined: Dec 2007
Posts: 325
Likes: 0
From: Lower Hudson Valley, N.Y.
Think there's a benefit of changing this on a 5.4 3v gas-job? I'm not a big K&N fan. Will this be a big warranty issue?
Later...
Brewster...
Later...
Brewster...
Last edited by Citypol86; Nov 22, 2008 at 03:10 PM. Reason: Ommission
Posting Guru
Joined: Nov 2003
Posts: 1,949
Likes: 0
From: Near DC
It's not a warranty issue from what I have experienced, along with many others.
I don't care for K&N.....
Plus, they are inexpensive and you can get other filters at the same time.
Look here:
http://www.fleetfilter.com/Store_Vie...sel.asp?Cat=57
I don't care for K&N.....
Plus, they are inexpensive and you can get other filters at the same time.
Look here:
http://www.fleetfilter.com/Store_Vie...sel.asp?Cat=57
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Lead Driver
Joined: Jul 2005
Posts: 5,967
Likes: 7
From: Eccles, WV
K&N has been extensively debated in the forums here and the agreement was no. Something about the oil killing the sensor and gumming the turbo.
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Senior User
Joined: Dec 2007
Posts: 325
Likes: 0
From: Lower Hudson Valley, N.Y.
Later...
Brewster...
Of the next Riffraff East
Joined: Oct 2004
Posts: 8,679
Likes: 2
From: Concord NC
You will here more intake and turbo noise with an open element. You don't hear any sucking noise but will sometimes hear excess air coming back through the filter during hard accelerations.
