[M40eye]

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Just wanted to give y'all a heads up. The K&N air filter for the 2020 does not fit the 2021 M40i. As you can see in the picture, I have the tapered end all the way set in the air filter box, but it ain't gonna get any closer to filling that gap, lol.

[leon360x]

Thanks for the heads up, I think they have 2 different filters for X3, check the part number.

[M40eye]

Originally Posted by leon360x

Thanks for the heads up, I think they have 2 different filters for X3, check the part number.

There is not a part number for the 2021 X3 M40i on the K&N website, only the 2020.

[Regisss]

I have 2020 30d. What's your opinions... will I get some power or sound gain if I will put such a K&N air filter?

[freshxdough]

Originally Posted by TX M40i

There is not a part number for the 2021 X3 M40i on the K&N website, only the 2020.

Just to make sure as well, the 2018/2019 filter is different from the 2020 filter. Are you also saying that the 21 is different too? So a total of 3 filters? I have a k&n on my 2020. It would take me a little to find the part number to compare if you like. Their website didn't have it updated when I picked it up a year ago.

[JerryW235]

The correct part number for a 2021 X3 M40i is a 33-3134. Ordered one off of Ebay, and it's a perfect fit. On the K&N site it does not come up for a 2021, but does for a 2020.

The other model, # 33-3079, indicates that it is NOT for the B58D engine. Just think their website needs to be updated.

[M40eye]

The 33-3079 does not fit the 2021, I can attest to the that. If anyone wants one cheap, holler, half price It's never been used and waiting for a new owner.

And thanks for the info on the 21! You're right, K&N doesn't show that...how'd you find that out?

[JerryW235]

Originally Posted by TX M40i

The 33-3079 does not fit the 2021, I can attest to the that. If anyone wants one cheap, holler, half price It's never been used and waiting for a new owner.

And thanks for the info on the 21! You're right, K&N doesn't show that...how'd you find that out?

Just by searching their website for a 2021, and then for a 2020. Took a chance that if they do list a filter for a 2020, it would fit a 2021. Figured if it did not fit, I'd return it.

[GGEVOX]

^^^Thanks for sharing everyone for their findings.

[eX3Werks]

Just curious, how much did you guys pay for your filters? Im looking to order one for my 2018 and the shop says it has to be special order. $67 CAD.

[brettl]

What’s the main draw to the k&n? Can you feel a difference in the car? Better intake sounds? Better response? I threw one in my wife’s old a4 ages ago and had to pay for a new mass air sensor. Since then I’ve been hesitant...

[JerryW235]

Originally Posted by eric_88

Just curious, how much did you guys pay for your filters? Im looking to order one for my 2018 and the shop says it has to be special order. $67 CAD.

I paid $60 US plus tax on Ebay, almost $64 total.

[M40eye]

Originally Posted by eric_88

Just curious, how much did you guys pay for your filters? Im looking to order one for my 2018 and the shop says it has to be special order. $67 CAD.

If the one I have fits yours (33-3079), you can have it for $40 plus shipping. I can ship it tomorrow.

[SO8]

Originally Posted by Regisss

I have 2020 30d. What's your opinions... will I get some power or sound gain if I will put such a K&N air filter?

I doubt much of anything with a panel filter replacement. It may give a bhp or two but normally I have only used a filter to compliment a remap.

I stopped using filters when there was talk of the oiled ones transferring oil onto the MAF sensor. I stopped using dry ones when they appeared to let in too much cr** ! Stuck to standard and never been bothered since to change.

[eX3Werks]

That bad eh? I have it on my CLS and I haven't noticed any issues. But seeing how many people have issues it would be a matter of time. I might have to rethink putting it on the X3...

[Burr001]

Wanted to bump this to confirm fitment for MY22 X3M40i 33-3134 K&N AIR FILTER

@Rottweiler sry can't upload pics to PM you.

[Navypilot]

I used K&N filters in both a 911 and old Jensen Healy. I never felt that the benefits outwayed the process of cleaning and reoiling them. I went back to just replacing with OEM air filters.

[JDsX3]

Originally Posted by brettl

What’s the main draw to the k&n? Can you feel a difference in the car? Better intake sounds? Better response? I threw one in my wife’s old a4 ages ago and had to pay for a new mass air sensor. Since then I’ve been hesitant...

The problem with K&N (and other wet oiled filters) is that it is too easy to over oil the filter and then louse up the mass air sensor with oil blow by.

[AusX3]

I just purchase a new one every 12 months. Perfectly oiled and not much cost difference than factory

[Rottweiler]

Originally Posted by AusX3

I just purchase a new one every 12 months. Perfectly oiled and not much cost difference than factory

Define “baller” ⬆️

(Not sure re Aussie lingo but that’s a compliment)

[AusX3]

Originally Posted by Rottweiler

Define “baller” ⬆️

(Not sure re Aussie lingo but that’s a compliment)

It translates - I'm married to a Canadian

[suby01]

Originally Posted by AusX3

I just purchase a new one every 12 months. Perfectly oiled and not much cost difference than factory

Same. New KN every summer.