OEM oiled filters vs aftermarket non-oilled filters?

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I haven't really installed a new filter in my 2004 WRX in a while. It's my understanding that it generally doesn't do much damage, although it might possibly create a restriction. However, when I look at the typical dirt collection patterns on the pleats, it's only a fraction of the filter that loads up. The edges of the pleats seem to collect the most dirt, but then in certain areas the dirt collects deeper into the pleat. I found this photo online, which is typical of what I see: [Linked Image] The Subaru OEM filters were almost the same design over the years. The factory installed one was made in Japan and red. I bought a bunch of OEM filters (made in USA) from a dealer years ago and eventually ran out. The filter color was more yellow but still effective. Then the OEM seemed to be made in Mexico but looked as good as the others. But they were always lightly oiled and had a metal frame where there was some paper label on both of the longer sides of the rectangle. I'm thinking maybe aftermarket. I've seen the various rectangular box filters from Fram/Wix/Purolator/house brands and they seem to be simpler ones made of unoiled paper, no frame, a foam surround, and maybe a screen. Any issues with installing something like that vs an OEM?
 
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My Nissan Rogue was so oiled from the factory it fouled the MAF. Silly. I thought it was a PCV issue - but no. After dealing with driveability issues I cleaned the MAF on a whim with CRC maf cleaner and it ran fine in a couple days of adjusting coefficients. . I threw the OEM nissan filter in the STP box that replaced it and that box is now completely saturated with oil. I've had hit or miss on Fram and STP. One FRAM I bought for the wife's Forester hard plastic frame was so warped the airbox couldnt be closed. Some fibreglass were over tacky or waxed and caused a loss of WOT torque at high rpm. . Other applications have been fine. I liked the Toyota thick fuzzy spun polyester (?) filters.
 

y_p_w

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I remember buying filters for GM applications. This was back when one could actually find AC/ACDelco filters fairly cheap at Kmart. I remember a short cylindrical filter for a GM "space van" (Lumina APV in my case) was pretty cheap. It came lightly oiled in a cardboard box. And once the box was stored long enough, some of it would migrate out, crawl down the hard foam surround, and stain the box a little bit. However, it wasn't too bad. Every Subaru filter I've ever bought was oiled and wrapped in plastic. They weren't super oily, but definitely there was oil that showed up on the inside of the bag. On my 1995 Integra the factory filter (as well as every aftermarket other than K&N) used this these depth-type polyester/nylon/whatever fibers in pleats like you mentioned. I believe that's the type of media in the aftermarket filter I got for my wife's Civic.
 

y_p_w

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Finally broke down and bought a new filter at a dealer and installed it. Probably paid too much but I didn't really care about $3 here or there. The new one looks like the one in the photo. Orange foam, metal frame, no mesh (like a Fram), and a paper label on the long sides with the part number. I wrote down the date and mileage on the frame with a Sharpie. Turns out I did it the last time, which was nearly 5-1/2 years ago and about 55k miles ago. That was also the last filter from a stash I bought in 2004, which I recognized because it was labelled "MADE IN U.S.A." (new ones made in Mexico). I figure it shouldn't damage the engine if it's loaded up, but it probably affected performance. It was by far the dirtiest filter I've ever taken out of this car. It also looked like the pleats started bending a bit where they were the most heavily loaded, but the element was otherwise intact. I also forgot much of a PITA it is to get a 2004 WRX filter housing back in place with the filter installed. It has these tabs that fit into a slot, but with the filter in place it's hard to force it in there. I did it in front of my house, and a neighbor saw me fumbling with it asking if I needed help. This is kind of it, but the OEM filter has a rigid frame and doesn't bend like the one in this video.
 
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Fram doesn't make those Ultra air filters for cars that have oiled air filters as OE mad Most late-model Hondas' OEM air filters are oiled just like the Fram TG/Ultra
 

y_p_w

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Fram Ultra 4309 has a light oil on it has well... I know because I have bought one and it was obvious it had a light oil on it. It came in a sealed plastic bag for the obvious reason to keep it from prematurely drying out. Plus the filter was rather rigid and well put together. Having said that I don't blame you for getting a OEM air filter... The OEM air filter for my car are actually quite good as well in regards to construction. They cost $19.99. I'd bet your OEM air filter is likely very similar to the one that would go in my car.
 
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y_p_w

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Originally Posted by bbhero
Fram Ultra 4309 has a light oil on it has well... I know because I have bought one and it was obvious it had a light oil on it. It came in a sealed plastic bag for the obvious reason to keep it from prematurely drying out. Plus the filter was rather rigid and well put together. Having said that I don't blame you for getting a OEM air filter... The OEM air filter for my car are actually quite good as well in regards to construction. They cost $19.99. I'd bet your OEM air filter is likely very similar to the one that would go in my car.
I'm not sure what the deal is with the price. The Subaru MRSP is about $16. The dealer I went to was $19 for whatever reason, so that was the $3 more I mentioned. Years ago I bought 3 from 1stSubaruParts, which was a dealer in Washington state for less than $10 each and that stash pretty much lasted for years, although I used one bought in person at a Subaru dealer in Carson City, NV. For whatever reason when I've driven between Reno and Lake Tahoe I've gone there for a look and have bought several parts there because the prices were better than near home. I guess I could have just dropped in a Fram CA4309, which seems to be a fairly common filter shape for different carmakers, but Subaru OEM seemed to work rather well. They've made slight changes (manufacturing source, color) but the overall design doesn't seem to have changed at all. Oiled media, metal frame, labelled on both long sides, foam surround. If you look at the video showing an aftermarket filter being inspected, it flops around because it's only held in place by the foam.
 
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Yeah the dealer pricing is a bit on the high side. At least the air filter is really well made. Therefore making it worth it really. I grabbed a Fram Ultra air filter while at Walmart earlier and it was much more rigid vs the ca4309 air filter. I have heard the Nissan air filter is similar to the OEM for your vehicle. Almost makes me wonder if the same company makes them both..
 
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I have only been able to find 1 non OEM Honda air filter that is oiled, the Denso first time fit. Plus it is made in Japan. Very Dusty where I live.
 
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Originally Posted by zmelli
I have only been able to find 1 non OEM Honda air filter that is oiled, the Denso first time fit. Plus it is made in Japan. Very Dusty where I live.
Which Honda is it for? I thought all the Denso FTF filters were Chinese now.
 
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Originally Posted by slacktide_bitog
Originally Posted by zmelli
I have only been able to find 1 non OEM Honda air filter that is oiled, the Denso first time fit. Plus it is made in Japan. Very Dusty where I live.
Which Honda is it for? I thought all the Denso FTF filters were Chinese now.
93 Accord p/n 143-2020
 
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Why take the chance and screw with your MAF sensor? Oiled filters are too much trouble. Non-oiled are the way to go. Readily available, regular Fram and ACDelco air filters are more than adequate -- they're excellent.
 
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If OEM is oiled like Hondas, no harm in using the aftermarket one. The oil does help with fine particles though. It's only when some goober over-oils an K&N or similar filter but it's very easy to do unfortunately.
 
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The types of filter material and layers that are oiled will make a difference as too if oil can shed and how much. There are also filters from woven cotton not gauze like k&n use which makes it easier to get a uniform amount of oil across the filter. It also prevents the filter from shedding material like gauze can do.
 
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I haven't really installed a new filter in my 2004 WRX in a while. It's my understanding that it generally doesn't do much damage, although it might possibly create a restriction. However, when I look at the typical dirt collection patterns on the pleats, it's only a fraction of the filter that loads up. The edges of the pleats seem to collect the most dirt, but then in certain areas the dirt collects deeper into the pleat. I found this photo online, which is typical of what I see: [Linked Image] The Subaru OEM filters were almost the same design over the years. The factory installed one was made in Japan and red. I bought a bunch of OEM filters (made in USA) from a dealer years ago and eventually ran out. The filter color was more yellow but still effective. Then the OEM seemed to be made in Mexico but looked as good as the others. But they were always lightly oiled and had a metal frame where there was some paper label on both of the longer sides of the rectangle. I'm thinking maybe aftermarket. I've seen the various rectangular box filters from Fram/Wix/Purolator/house brands and they seem to be simpler ones made of unoiled paper, no frame, a foam surround, and maybe a screen. Any issues with installing something like that vs an OEM?
So even a cheap new filter is better than pushing it with an old filter. If $5 to $8 is too much to ensure from engine failure then maybe you need to rethink... I have a brother that felt that not changing the oil filter on a late model Volvo he bought new was a waste of money as long as he changed the oil. Well, at around 40,000 miles the engine blew up. The Swedes think a lot of their engines... $10,000 later my brother has never lived it down ... choose your poison!!!
 
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