Questions Regarding Benefits of Air Box Mod / Silencer Removal?

[Exproblems]

I've been thinking about doing the Air Box Mod / Silencer removal for a while now having read through some of the past posts on this mod to see about getting better gas mileage or MPG's. I know how to remove the air box and the silencer, but what I want to find out is, can the "Silencer" (air intake nozzle) be re-installed without any major modifications to it after having removed it? Does the Silencer or parts to it break after "twisting" it out of the air box?
I'd also like to hear how many people that did this mod to their Explorer's, got better gas mileage after having done this mod? Currently, I get around 11-13 mpg in the city which sucks, worse in winter and snow! On the NYS Thruway 65 MPH +, I get 15-16 MPG's. My Explorer has had numerous tune up stuff done to it within the last 2 years or 10k in miles, including I installed new double platinum plugs a month ago and a new set of Bridgestone Dueler tires. I'm about out of options to try to increase the gas mileage in this thing. Thanks in advance to any and all who reply!

 

[sfhess]

Seeing as the whole system was engineered by Ford to operate in the most efficient manner, it's probably best to leave it alone. Unless you are in love with induction noise.

 

[Exproblems]

Seeing as the whole system was engineered by Ford to operate in the most efficient manner, it's probably best to leave it alone. Unless you are in love with induction noise.

The type of reply you left me wasn't quite what I was looking for. I also know about the increased air flow noise when the silencer is removed. By efficient, do you mean the 11-13 MPG I get in the city? BTW, are you talking about the same great Ford engineers who designed the "blend door actuators, cracked rear applique, timing chain cassettes, air recirculation doors, vacuum control issues, door ajar switches, crappy transmissions(no dipsticks either), etc. etc.? See where I am going with this as far as Ford engineers are concerned? If you want to say Ford engineers did a great job of "intentionally" designing some really crappy parts to go in their vehicles then I'd give them an A+! The Silencer might be one of them, that is why I am trying to find out how many people gained MPG's by removing it.

 

[D Hook]

Where is this silencer located? Is it the rectangular box that goes on the side of the air hose downstream of the MAF? Or is it located inside the airbox?

 

[Exproblems]

Where is this silencer located? Is it the rectangular box that goes on the side of the air hose downstream of the MAF? Or is it located inside the airbox?

The air filter box intake "Silencer" AKA "Fresh Air Intake" (looks like rounded plastic tubing) connects to the air filter box in the front of the air box and then connects to a hole in the support wall below the backside of the passenger side headlight. In the link below, look at post #10 for a cut-a-way view of the Silencer location and what to look for.

http://www.explorerforum.com/forums/showthread.php?t=311988

 

[n2epv]

The silencer is just a 'friction fit' into the front of the airbox. I have had mine out several times - just pull the bottom section of the airbox out of the truck. There are tabs on the bottom and outboard side that fit into rubber grommets. One good pull in the right direction, and it will pop out with no damage to anything.

I did some testing with the silencer on and off. Aside from more noise with it off, there seems to be a 1-2 MPG loss in the summer (and no change in cooler temps). Probably because without the silencer, the engine breaths warmer under-hood air causing the PCM to retard the timing.

My '04 V8 will deliver the EPA estimate all day long on trips - 18 MPG highway. Just don't ever exceed about 70 MPH. Above that it drops like a rock.

 

[D Hook]

Looks like mine has already been removed by a previous owner. Thanks for the info guys.

I just removed the CAI kit that came on my Explorer when I bought it. I want to see if there's a major difference in gas mileage using the CAI vs. the stock air box. I don't care for the CAI because it has the washable filter and don't care to mess with washing and oiling the air filter. If the stock setup gives the same mileage or close to it, I'll stick with it. Besides the CAI kit looks kinda' cheesy with the blue connecting tubes and the aluminum pieces leading to the throttle body. Just my opinion. If mileage drops drastically, I'll put the CAI back on and just try to ignore the looks of it.

 

[Exproblems]

The silencer is just a 'friction fit' into the front of the airbox. I have had mine out several times - just pull the bottom section of the airbox out of the truck. There are tabs on the bottom and outboard side that fit into rubber grommets. One good pull in the right direction, and it will pop out with no damage to anything.

I did some testing with the silencer on and off. Aside from more noise with it off, there seems to be a 1-2 MPG loss in the summer (and no change in cooler temps). Probably because without the silencer, the engine breaths warmer under-hood air causing the PCM to retard the timing.

.

Thanks for the info. Some have even said to lubricate the grommets prior to twisting the silencer out of the air box. Makes it easier to remove.
You are the first I've read that lost MPG's with the silencer removed. A few had stated a 1-2 MPG gain with it removed and others noticed no change or benefit at all. Your point about the engine breathing warmer air with the silencer removed makes perfect sense since it is very hot under the hood. The air intake wouldn't be funneling cooler air that flows thru the front grill as you drive with the silencer/fresh air intake removed. Not sure what to do with it yet.

 

[Exproblems]

I don't care for the CAI because it has the washable filter and don't care to mess with washing and oiling the air filter. .

I'm am probably going to wash my K&N drop in filter for the first time by the end of this summer. I plan on using a 5 gallon bucket filled with water and Dawn dish washing detergent and just submerge it in the bucket for a half a day, then rinse and dry it out for a day or so. I'll just put my previously new Fram air filter back in the air box until the K&N filter is done drying. My mechanic with 35+ years of automotive repair experience says he doesn't re-oil the K&N filter in his truck after he cleans it. Just puts it back in his truck dry. I may give that method a try on mine as well and see if it makes any kind of difference.

 

[Blue91Ex]

My mechanic with 35+ years of automotive repair experience says he doesn't re-oil the K&N filter in his truck after he cleans it. Just puts it back in his truck dry. I may give that method a try on mine as well and see if it makes any kind of difference.

That would make it get better air flow, but capture less contaminates. I have had issues with lawnmowers after cleaning the airfilters and re oiling them and having too much oil in them (just foam, usually you squish them between paper towel until they are dry to the touch) and it couldnt get enough air to start until i soaked up more of the oil i put in the filter. I would assume this basic idea is the same with washable truck air filters. Dirt etc sticks to oil well but it restricts some airflow.

All in all i would suggest still oiling it but very little if you want to keep the better airflow.

 

[Exproblems]

That would make it get better air flow, but capture less contaminates. I have had issues with lawnmowers after cleaning the airfilters and re oiling them and having too much oil in them (just foam, usually you squish them between paper towel until they are dry to the touch) and it couldnt get enough air to start until i soaked up more of the oil i put in the filter. I would assume this basic idea is the same with washable truck air filters. Dirt etc sticks to oil well but it restricts some airflow.

All in all i would suggest still oiling it but very little if you want to keep the better airflow.

Problem with over oiling a K&N filter is that I don't think you can squeeze out the excess oil like you can with a foam lawnmower filter. As you said, a light coat of oil would be better when re-oiling a K&N filter. As far as going with a dry filter, I don't see a real problem with it since Fram air filters are a dry paper element and I've used them for years before going with the K&N filter. I would think the K&N filter element is a higher quality element than the ones in a Fram air filter. If I remember right, the K&N filter element is made out of cotton, not paper.

 

[D Hook]

I'm am probably going to wash my K&N drop in filter for the first time by the end of this summer. I plan on using a 5 gallon bucket filled with water and Dawn dish washing detergent and just submerge it in the bucket for a half a day, then rinse and dry it out for a day or so. I'll just put my previously new Fram air filter back in the air box until the K&N filter is done drying. My mechanic with 35+ years of automotive repair experience says he doesn't re-oil the K&N filter in his truck after he cleans it. Just puts it back in his truck dry. I may give that method a try on mine as well and see if it makes any kind of difference.

Is this a K&N cone shape or flat?

I'll be interested to hear the results you get. Please keep us posted.

 

[caspian65]

When we got our '02 new, I bought a MAC cold air intake for it, with the only reason being that I hoped it might help the mpg a little. I don't remember if it saved much, but there are 2 things I remember about it... 1) The acceleration felt just a touch more zippy, 2) It was very loud at idle.

Think the CAI was on there for maybe 125k miles, I took it off and put the stock setup back on. Still have the CAI setup, but just don't like how loud it was.

 

[tursky4]

I have removed the "silencer" from the air box but not done the complete air box mod and i dont think im going to because after removing the "silencer" i have gained 1-2 mpg consistently over the past 8 to 10 fill ups.. i would recommend removing the silencer at the least...

 

[Exproblems]

Is this a K&N cone shape or flat?

I'll be interested to hear the results you get. Please keep us posted.

It's the flat, drop in style K&N filter. I'll let you know how I make out with the cleaning once I get around to doing it, hopefully soon.

 

[Exproblems]

I have removed the "silencer" from the air box but not done the complete air box mod and i dont think im going to because after removing the "silencer" i have gained 1-2 mpg consistently over the past 8 to 10 fill ups.. i would recommend removing the silencer at the least...

Thanks Tursky, that's good to hear you "gained 1-2 MPG" after removing the air box Silencer. During those 8-10 fill ups, were you driving in cold or hot weather conditions?

 

[Exproblems]

Is this a K&N cone shape or flat?

I'll be interested to hear the results you get. Please keep us posted.

I cleaned my K&N air filter this morning for the first time. It came out good and much cleaner looking than it was. I sprayed the filter element with brake cleaner first to break down the oil, only leaving the brake cleaner on the filter element for no more than a minute before I dunked the filter into a bucket of warm water and Dawn dish soap. I didn't want the brake cleaner to dry on the filter element. (I used brake cleaner because Advance Auto only had $14.99 bottles of K&N filter cleaner there and I figured why spend the money when I won't be cleaning it all that often.) I let the air filter soak in the bucket for around 30 minutes while I grass trimmed the creek bank in my backyard. Once done with the grass trimming, I went and rinsed off the air filter with a garden hose, flushing it out good. The filter element now looks white-ish in color. I then blew out the remaining water in the air filter with my leaf blower and dried it fully using a hair dryer. I did it this way because it got cloudy all of a sudden, no sun to dry it. When I went to empty the bucket of water and Dawn solution, the water color was now red-ish in color from the filter oil.

I'm going to try an experiment and put the filter in dry(no oiling) and see if my gas mileage goes up, down or stays the same. If the MPG's go up, I'll keep the filter dry, if they go down or stay the same as before with the filter oiled, I'll then oil it back up lightly. I'll top off my gas tank in the morning and see what happens.

 

[2Trux]

I'm going to try an experiment and put the filter in dry(no oiling) and see if my gas mileage goes up, down or stays the same. If the MPG's go up, I'll keep the filter dry, if they go down or stay the same as before with the filter oiled, I'll then oil it back up lightly. I'll top off my gas tank in the morning and see what happens.

I believe that not oiling the K&N filter makes it only slightly more effective than having no filter. The oil does the filtering, the cloth is there to hold the oil. As the dirt builds up on the oil and gets soaked with oil the filter becomes more effective.
Go to the K&N site and see what they say about how the filter works.

 

[tursky4]

Thanks Tursky, that's good to hear you "gained 1-2 MPG" after removing the air box Silencer. During those 8-10 fill ups, were you driving in cold or hot weather conditions?

well it was during late june until now in nw pa... it was probably between 80 and 90 every day... soo mostly hotter weather but nothing like arizona or texas...

 

[Exproblems]

I believe that not oiling the K&N filter makes it only slightly more effective than having no filter. The oil does the filtering, the cloth is there to hold the oil. As the dirt builds up on the oil and gets soaked with oil the filter becomes more effective.
Go to the K&N site and see what they say about how the filter works.

Thanks for the info. I haven't noticed any great increase in gas mileage since I cleaned my K&N air filter last week and installing it dry, so I'll be oiling it back up in a few days and see what happens then. I've been to the K&N web site and do know what the purpose of the oil is to the filter element. I was just trying something my mechanic said he does with his K&N air filter.