Engine air filter OEM vs replacement

When replacing my engine air filter I noticed significant difference between the factory-installed filter (right in photo) and the replacement sold by the Toyota dealer. The replacement is half the thickness and has no pre-foam (or whatever you call it). Not sure what’s going on here. Couldn’t really get a straight answer from the dealer. I’ll be watching my performance and mileage, but I’m willing to bet it all comes down to $$$.

 

The numbers printed on them are different in your photo. This one matches the one on the right:

https://www.ebay.com/itm/3542113258...1291&msclkid=826d3b902b4912802e65589039ac48a8

I checked the Wix 49350 air filter I got for the 4R and it looks just like the one on the right in your photo.

 

I just bought two new filters from a dealer in Colorado Springs and they are the thicker one with the foam layer. The dealer used the number from my OEM filter and the new ones are exactly the same. I had recently picked up an STP brand replacement from the auto parts and that one had fewer pleats and no foam. I couldn't tolerate the downgrade on something that important.

 

I bought a replacement from the dealership a couple of years ago. It was as thick as the original but without the scotch bright pad. Different number. The one that comes original is a Japanese.
If they just transitioned to the thinner design I would be reluctant to buy.

 

the air filter is the wrong filter small DENSO ... the toyota air filter is a double the air flow ..

 

17801-38051 is the P/N for the thicker model with the prefilter.

 

Good luck finding a 17801-38051, dealer's only have 17801-yzz13 now.

 

Just ordered one a few days ago, must have more backstock than your area.

 

I have had so much frustration with counterfeit stuff on Amazon that I now just buy all auto consumables at the local parts store.

Wix or Napa Gold (which I think may be Wix for some line anyway) every time.

Jason

 

You are right, it seems that Amazon is becoming the new Fry's electronics - selling returned items as new, and or refurbished items as new. I am very careful with what I get on Amazon. That Prime membership just might be going 'bye bye'.

 

I tried ordering from a couple of different dealers online about a month ago, both sent me emails back saying they weren't in stock and do you want the replacement yzz13 filter instead. So maybe they do have them back in stock now.

 

Purolator One

$19 A36122 PurolatorONE Advanced Engine Air Filter Compatible With Select Toyota and Lexus

A36122. It looks almost exactly like the OEM one, same larger size, with the foam pre-filter.

 

This Product Is No Longer Available for production.... Checked with toyota parts
So grab the thick one wherever you can find one.

I guess the thinner ones are cheaper to produce

 

I just ordered the 17801- 38051 from Larry Miller Toyota parts. I really hope that they do not stop production on these !!

 

Yeah, the dealer told me the thinner ones is all they had available the last time I got one. Thanks for the purolator part number. I think I’ll be going with aftermarket airfilters from now on.

 

Just out of curiosity beside cost saving exercise by Toyota.

Is there any technical reasoning to increase engine air flow to boost 4R performance/Slow pickup - by making Toyota Air filter thinner

Has anyone tried both to see any significant changes in engine sound and accelerations etc.

17801-38051 Versus 17801-yzz13

Based on past
experiences with very thick aftermarket air filters on different model vehicles - There were adverse affects with restricted engine air flows. Acceleration became poor.

Cheers

 

I am running the thinner one now but have the thicker one coming . I will post results after changing to the thicker one.

 

I would not assume that the new thinner filter would flow faster. They might, but that would mean it filters substantially less.

All things equal, im pretty sure it’s the opposite. Given the same filtering media, more/deeper pleats makes airflow less restricted, not more restricted.

The only reason high performance filters like a K&N flow with low resistance, is because the filtering media itself doesnt really filter anywhere near as much. You can see daylight through some of those.

The best way to increase airflow (or reduce resistance) while maintaining high filtering capability, is to increase the amount of pleats and increase their depth in order to create as much surface area as possible.

For whatit’s worth, when I changed from the factory original to the new thinner OEM replacement element, I did not notice a difference in sound or performance.

 

Interesting. I ordered a supposedly OEM Toyota a year or two ago from Amazon, and the one that arrived looked like the one on the right. I know for a fact it definitely had that extra foam element attached to it.

 

i just started buying K&N filters for air box and cabin air. Just for pure convenience of reusable and cleanable.

 

I'm not certain, but I believe one purpose for the thin layer of foam is to catch bugs and other particles, keeping those from embedding into the pleats. It's not able to filter much better than that.

 

Besides the purolator filter, NAPA sells the thick one with prefilter.

I bought one today since I recently did a ton of driving in heavy dust.

The pleats per inch are less in the new one, but it’s twice as thick, so ultimately it has more filtering capacity.

 

Bought a WIX 49350 at O'Reilly yesterday, thickness is the same as the pre-revision filter and includes the foam pre cleaner element.

 

Do they make a k&n to fit the factory air box?

 

This is the one i got, fits perfect. I can only assume that it's the same for all 5th gens.

https://www.knfilters.com/air-filters/toyota/4runner/4.0l-v6-gas/2018

 

Happy Friday. This is a very interesting topic

Does anyone know which of the Air filter types comes delivered with the 2022 4Runners.

17801-38051 OR 17801-yzz13

That would also shed some light on the reasoning.

The replacement parts # of some of the 2022 4R drivetrain are completely different from previous years

 

My 22 ORP came from the factory with 17801-38501

 

Thanks for the swift reply @ hvac guy
Wonder why the Toyota is now superseding with the thinner versions (especially for those off-roading in dust regions) - 17801-yzz13

 

I went to my usual shop to get the oil changed, and they changed the air filter also, they used the thick one. I asked about the thinner on superseding the other and he said he did not know anything about that, but has both in stock, and can get both. I asked about the AEM dry filter because i saw it on the shelf, and he said he does not recommend it in the Runner because it does not fit tight enough to keep dirt and dust from getting in around the edges.

 

Total guess, but I bet the thicker filter is overkill for the US market.

I like the idea of the thicker factory filter, but cant imagine Toyota is making a mistake with superceding the filter with this thinner one.