what is this mod
what is this mod
Logistics Pro
Joined: Nov 2006
Posts: 3,671
Likes: 367
From: Fallon,NV & Bainbridge OH
Welcome to the site, you will find it full of information.
Go to the home page and type the number in the search engine and you will get more info than you could ever want. But basically it is a pleated paper filter that replaces the stock filter and box. I personally run a K&N cold air kit that is a subject of much discussion on here but I have none of the problems people associate with the K&N. I guess you have to be smarter than the filter, any filter system will give you problems if it is not maintained and installed correctly.
Go to the home page and type the number in the search engine and you will get more info than you could ever want. But basically it is a pleated paper filter that replaces the stock filter and box. I personally run a K&N cold air kit that is a subject of much discussion on here but I have none of the problems people associate with the K&N. I guess you have to be smarter than the filter, any filter system will give you problems if it is not maintained and installed correctly.
Postmaster
Joined: Jun 2006
Posts: 2,647
Likes: 0
From: Fulltime RVer
Originally Posted by smoke'm
I'm new to the site , so what is this 6637 mod everyone has listed
Post #6 on the thread below has an extensive list of links...
Which air filter
https://www.ford-trucks.com/forums/670724-which-air-filter.html
... and here's a recent one...
6637 Change interval? What do you do?
https://www.ford-trucks.com/forums/675108-6637-change-interval-what-do-you-do.html
If you read even half of these links, you'll know more about a 6637 than 99% of the people on this forum!
Posting Guru
Joined: Aug 2007
Posts: 1,852
Likes: 1
From: Sonoita Hills, AZ
With the K&N dirt passes thru the filter, nomatter how it is maintained. Someone has a link showing the tests. If you actually "look" at the tests, you may change your mind. I did. Inspect your intake tube for dust. I live on a dirt road, theres dust in my tube and its not from lack of maintanence or installing a drop in incorrectly.
Fleet Owner
Joined: Jun 2004
Posts: 25,090
Likes: 1,112
From: Rio Rico, AZ.
This picture should explain it.
The filter is NAPA part number 6637. You have to remove the air filter housing to get it to fit. It does a MUCH better job of filtering than the stock Ford air box.
.
The filter is NAPA part number 6637. You have to remove the air filter housing to get it to fit. It does a MUCH better job of filtering than the stock Ford air box.
.
PSD Addict
Joined: Nov 2006
Posts: 731
Likes: 0
From: Michigan
Originally Posted by rugermack
With the K&N dirt passes thru the filter, nomatter how it is maintained. Someone has a link showing the tests. If you actually "look" at the tests, you may change your mind. I did. Inspect your intake tube for dust. I live on a dirt road, theres dust in my tube and its not from lack of maintanence or installing a drop in incorrectly.
Exactly! It doesn't take a brain surgeon to Properly maintain a filter and there is no black magic. K&N flows dirt, plain and simple. I've replaced two 4-wheeler motors because of K&Ns, I have seen the tale-tale trail of dirt into the carb with PROPERLY maintained K&Ns. I guess you have to figure out if your motor is worth the risk.
Last edited by TurtleRacing; Nov 21, 2007 at 07:38 AM.
Posting Guru
Joined: Aug 2007
Posts: 1,852
Likes: 1
From: Sonoita Hills, AZ
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PSD Addict
Joined: Nov 2006
Posts: 731
Likes: 0
From: Michigan
Originally Posted by Kwikkordead
This picture should explain it.
The filter is NAPA part number 6637. You have to remove the air filter housing to get it to fit. It does a MUCH better job of filtering than the stock Ford air box.
.
The filter is NAPA part number 6637. You have to remove the air filter housing to get it to fit. It does a MUCH better job of filtering than the stock Ford air box.
.
It looks like you are just clamped right on the filter w/o exhaust tubing, has that held on for you?
I'm also curious, I was thinking about putting the filter gauge in the exhaust tubing between the filter and intake tube, will this work?
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Fleet Owner
Joined: Jun 2004
Posts: 25,090
Likes: 1,112
From: Rio Rico, AZ.
Originally Posted by TurtleRacing
It looks like you are just clamped right on the filter w/o exhaust tubing, has that held on for you?
I'm also curious, I was thinking about putting the filter gauge in the exhaust tubing between the filter and intake tube, will this work?
I'm also curious, I was thinking about putting the filter gauge in the exhaust tubing between the filter and intake tube, will this work?
And yes I did clamp the rubber tube to the filter.
Remove the boot from the engine. COMPLETELY degrease the clamping area that goes onto the filter. Use whatever means necessary to get it down to squeaky rubber. Do the same for the flange on the air filter.
Put your arm down inside the boot and use both hands to install the boot to the filter and clamp it down. Then install the whole assembly back onto the engine.
Fleet Owner
Joined: Jun 2004
Posts: 25,090
Likes: 1,112
From: Rio Rico, AZ.
Rugermack, I have the AIS Ford HD air filter system now.
The only reason that I removed the 6637 and put that on instead is because the noise coming out of the intake was driving me crazy and I wanted to quiet things down a little. My truck is noisier than average inside the cab of the truck.
The only reason that I removed the 6637 and put that on instead is because the noise coming out of the intake was driving me crazy and I wanted to quiet things down a little. My truck is noisier than average inside the cab of the truck.
Posting Guru
Joined: Aug 2007
Posts: 1,852
Likes: 1
From: Sonoita Hills, AZ
Sorry, I thought you had a 6637 installed. I don't realy like all the extra noise either. That would be my only complaint about the 6637 mod. This weekend I'm going to see if I can do a little insulation or something to help it out (noise).
Senior User
Joined: Sep 2006
Posts: 484
Likes: 0
From: CT
Originally Posted by Kwikkordead
I would put it here.
And yes I did clamp the rubber tube to the filter.
Remove the boot from the engine. COMPLETELY degrease the clamping area that goes onto the filter. Use whatever means necessary to get it down to squeaky rubber. Do the same for the flange on the air filter.
Put your arm down inside the boot and use both hands to install the boot to the filter and clamp it down. Then install the whole assembly back onto the engine.
And yes I did clamp the rubber tube to the filter.
Remove the boot from the engine. COMPLETELY degrease the clamping area that goes onto the filter. Use whatever means necessary to get it down to squeaky rubber. Do the same for the flange on the air filter.
Put your arm down inside the boot and use both hands to install the boot to the filter and clamp it down. Then install the whole assembly back onto the engine.
Postmaster
Joined: Jun 2006
Posts: 2,647
Likes: 0
From: Fulltime RVer
Originally Posted by rugermack
kwik, you need one of those fancy covers from f250 for that 6637.
Hotshot
Joined: Nov 2006
Posts: 11,286
Likes: 263
From: North of Greenville
Ernest, it is supposed to get dirty... teh cover just keeps out the grossly large stuf like pieces of leaves, etc. It also helped the bird that came through my zoodad keep from getting its beak or claws tangled in the expanded metal surface on ym filter and potentailly tearing a hole in the paper. As for air flow restriction, I have not been able to tell any difference in mileage or SOTP feel or pedal response when I have run it with and without the cover.
I guess you could get a really heavy duty thick canvas that would tighten it down a bit, but that wasn't my goal or observation with the ones I'm making.
I guess you could get a really heavy duty thick canvas that would tighten it down a bit, but that wasn't my goal or observation with the ones I'm making.