6637 absorbs moisture???
Fleet Mechanic
Joined: Dec 2010
Posts: 1,546
Likes: 9
From: Wellington, Co
What, in London fog? Seriously, any filter can absorb moisture, but unless you drive through water a 6637 won't be worse. The fact that it's open could also allow it to dry quicker, right?
Cargo Master
Joined: Jul 2011
Posts: 2,680
Likes: 983
From: Walpole, MA
I know Donaldson makes a version of the 6637 for high moisture environments but it is spendy.
I believe one of the filter socks is hydrophobic as well... I have the RiffRaff sock which is not but does help keep the element clean.
Personally, I can only say I have been running open element air filters on all sorts of vehicles for 400-450K miles or so.... never had an issue. Maybe if I lived in a warmer, more humid environment like a Brazil rain forest I think about getting one but it would not be worth it for me in SE Mass.
I believe one of the filter socks is hydrophobic as well... I have the RiffRaff sock which is not but does help keep the element clean.
Personally, I can only say I have been running open element air filters on all sorts of vehicles for 400-450K miles or so.... never had an issue. Maybe if I lived in a warmer, more humid environment like a Brazil rain forest I think about getting one but it would not be worth it for me in SE Mass.
Locomotive breath
Joined: Jan 2006
Posts: 1,354
Likes: 1
From: Mid Oh. Ponderosa
We drove thru a driving rain storm in Kentucky 7 years ago and I checked it when we stopped for the nite 'cause I was concerned about it, and it was bone dry. This was right after I put it in and before Pete started making the covers for them.
Seems to me the competition doesn't like them because they are an inexpensive alternative to their high priced units.
Seems to me the competition doesn't like them because they are an inexpensive alternative to their high priced units.
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Hotshot
Joined: Nov 2006
Posts: 11,288
Likes: 269
From: North of Greenville
Ditto to all the comments above. I've driven over 120K miles in the Deep South summer heat & humidity, including highway drives through frog-strangling downpours... never a wet filter element yet.
Sounds like someone may have either gone mudding or been careless with the water hose while washing down the engine bay and left it warm and wet with no attention for a while. Also may have had some moisture contamination issues in a box that is kept in a non-dry area and discovered it when getting ready to replace an element. No doubt, a damp filter element can be a problem because the paper can come apart end get ingested into the turbo wheel, but for me, conventional daily driving has never shown this to be a real concern in the real world.
Sounds like someone may have either gone mudding or been careless with the water hose while washing down the engine bay and left it warm and wet with no attention for a while. Also may have had some moisture contamination issues in a box that is kept in a non-dry area and discovered it when getting ready to replace an element. No doubt, a damp filter element can be a problem because the paper can come apart end get ingested into the turbo wheel, but for me, conventional daily driving has never shown this to be a real concern in the real world.
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i ain't rite
Joined: Mar 2005
Posts: 65,630
Likes: 5,638
From: Marlboro Mental Hospital.
i just changed the 5 year old 6627 in my 02 a few months ago, and it still looked like new.
the Pete's cover on the other had was black from keeping all the crap out of the filter.
i have to wash the cover every year.
the Pete's cover on the other had was black from keeping all the crap out of the filter.
i have to wash the cover every year.
Senior User
Joined: Aug 2012
Posts: 307
Likes: 0
From: thornton CO
I took the truck through a car wash and thought i'd have a look at the filter as soon as I got out and sure enough it was wet on the top. The water seemed to run down the (gutter?) of the fender and was sucked in while idleing. And their was also suds on top of the wheel well liner, the filter was a little wet there too. I think i'll try some weather strip in the seam of the hood and fender.
Lead Driver
Joined: Feb 2000
Posts: 5,374
Likes: 46
From: Palm Bay, Florida
Guys, I am probably the only real nay-sayer on the 6637s
I personally run either a Purolator PURE ONE or Fram TOUGH GUARD filter in my stock air box, I get excellent oil reports from Blackstone that indicate and say that my air filter is working GREAT.
The PURE ONE and TOUGH GUARD are becoming hard to find, I watch Ebay and stock up when I can.
I personally run either a Purolator PURE ONE or Fram TOUGH GUARD filter in my stock air box, I get excellent oil reports from Blackstone that indicate and say that my air filter is working GREAT.
The PURE ONE and TOUGH GUARD are becoming hard to find, I watch Ebay and stock up when I can.
Senior User
Joined: May 2011
Posts: 454
Likes: 0
From: Portland, OR
Running the 6637 in the Pacific NW. It rains about 6 days a week here in the winter on average and mold/moss are real problems in yards, RVs, roofs, just about everywhere you can imagine. That being said, never had any trouble with the 6637.
I was also concerned about the space at the hood joint but the water seems to hit the channel and roll downhill to the front of the engine compartment without hitting the filter.
I was also concerned about the space at the hood joint but the water seems to hit the channel and roll downhill to the front of the engine compartment without hitting the filter.