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air-cleaners

K&N RX-4040-1 - Air Cleaner Assembly

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$76.49

$138.99

You save: $62.50 (45%) off MSRP

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Ships within 5 business days

This is a universal fit product

  1. That means this product doesn’t have fitment for any specific vehicle.
  2. If fitment is applicable for your application, be sure to check compatibility with the other components.
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About this product

Part #: RX-4040-1

K&N XStream Top Universal Air Filters take performance to the next level with the addition of a filter within the filter's top adding more filter area for higher air flow and a longer service interval. The XStream Air Filter provides awesome air flow and outstanding filtration. When racing, in any environment, racers need all the protection and airflow they can get. K&N delivers. All K&N universal air filters are constructed with ultra-strong molded pliable rubber flanges which absorb vibration and allow for secure attachment and can also be stretched for up to 1/16 inch (1.5mm) to fit in-between sizes. K&N universal air filters are washable and reusable.

More Details

Air Filter Large End Diameter4 in (102 mm)
Carb/Air Horn Dia. (in.)2.4375
Diameter Outside (in.)4
Filter Re-Oiling Amount0.62 oz (18 ml)
Flange Angle0 degrees
Flange Offset0 in (0 mm)
Flange TypeCentered
MaterialRubber Base
ShapeRound
Top StyleX-Stream
Additional Documents
  1. Technical Bulletinpdf
  2. Installation Instructionspdf

See what our community says about kn products

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What made you choose this particular product?
Needed an air filter upgrade in the mean time before I drop a intake in it. Trust K&N
Is this your first time buying from this brand? Did you consider other brands?
I looked at a couple of other brands, but not a lot of them had a lot of information on them. I have used K&N in the past and like the products.
View on Mark's build
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What made you choose this particular product?
Big diameter intake pipe, heat resistant box and good filter
View on Danny's build
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What made you choose this particular product?
Heard it was a good first mod for the car
Is this your first time buying from this brand? Did you consider other brands?
Yes
Was it easy to install? Any installation tips that will help others?
Yes
View on Ryan's build
product page reviews icon 0product page reviews icon 1product page reviews icon 2product page reviews icon 3product page reviews icon 4
What made you choose this particular product?
Performance and price
Is this your first time buying from this brand? Did you consider other brands?
Yes first time, would again
View on Josh's build
Joe Cipriani III

1.4k

Joe Cipriani III
2012 BMW 1 Series
product page reviews icon 0product page reviews icon 1product page reviews icon 2product page reviews icon 3product page reviews icon 4
What made you choose this particular product?
It was at my local Advance Auto Parts.
Is this your first time buying from this brand? Did you consider other brands?
No and Yes. aFe was the other but since the K&N kit was local I decided to go with that.
Was it easy to install? Any installation tips that will help others?
Yes. All you do is spray, wash away and apply the oil.
Once you've had a chance to use the product, did it meet your expectations?
It kept the intake clean so yes.
Any additional comments?
I would plan to have the intake dry overnight or have it sit on a heater. You need to have the intake completely dry or the oil would adhere and it takes forever to dry.
View on Joe's build
California prop 65 warningWARNING: Cancer and Reproductive Harm www.p65warnings.cs.gov

*Some manufacturer restrictions apply.

About K&N

K&N Engineering in Riverside California is the world's leading manufacturer of washable performance air filters and air intake systems. K&N invented the reusable high flow cotton air filter in 1969 and has been perfecting the technology ever since. K&N is a world class filtration company selling air filters, oil filters, and air intakes in over 30 countries. K&N sells over 5,000 products designed for cars, trucks, motorcycles, engines, and industrial applications. From their Million Mile Warranty to their Consumer Protection Pledge, K&N stands behind their products and their consumers 100%. The distinctive K&N logo represents performance from one of the original performance companies.

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Based in California with 3 warehouses across the country, we’re sending out shipments everyday of the week, even Saturdays. Because your next mod shouldn’t have to wait.

+ FREE GROUND SHIPPING ON U.S. ORDERS OVER $99
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