K&N® 33-2181 - 33 Series Panel Air Filter

4.51 review / Item # mpn1920847
K&N® - 33 Series Panel Air Filter
K&N® - 33 Series Panel Air FilterK&N® - 33 Series Panel Air Filter Installation InstructionsK&N® - 33 Series Panel Air Filter Dyno ChartK&N® - 33 Series Panel Air Filter InformationK&N® - Cleaning GuideK&N® - WarrantyK&N® - Air Filter Overview 602x420Made In USAK&N Authorized Dealer
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Product Details

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K&N Air Filters

33 Series Panel Air Filter by K&N®. Filter Material: Cotton Gauze. Filter Re-Oiling Amount: 1.21 oz (36 ml). Height: 1.25" (32 mm). Outside Length: 13.688" (348 mm). Outside Width: 5.188" (132 mm). Includes: 1 Air Filter. K&N's replacement air filters are designed to increase horsepower and acceleration while providing excellent filtration. We make over 1,200 different replacement air filters for the majority of vehicles on the road. These filters are washable and reusable and are custom designed to fit into your existing factory air box. Their drop-in design means adding performance is simple. With most vehicles you simply remove the disposable air filter and replace it with a K&N. See applicable instruction sheet for details. Our stock replacement air filters for street vehicles are covered by our famous K&N Million-Mile Limited Warranty and will be the last air filter your vehicle will ever need.

Notes: 2 Required.

K&N - F.A.Q.K&N - Air Filter CleaningK&N - Warranty


  • Improves engine airflow
  • Increases horsepower and acceleration
  • Superior filtration without reduced airflow
  • Reduces maintenance costs
  • Washable and reusable
  • Get up to 50,000 miles between cleanings under normal driving conditions
  • Emissions legal in all States
  • Backed by K&N's Million Mile Limited Warranty

Most air filters on the market are a compromise. Many high-performance filters deliver better airflow, but sacrifice filtering ability and engine protection in the process. OEM filters, which are usually made of paper, filter adequately but at the expense of airflow. And airflow decreases as these air filters become dirty. Not so the K&N air filter. K&N air filters increase airflow without decreasing filtration ability, and the increased airflow remains consistent throughout the filter's service interval. The secret is in the K&N filter's construction.

K&N's initial goal was to develop a filter that would deliver increased airflow during dirty, dusty off-road racing conditions. Increased airflow improves the efficiency of the combustion process, increasing horsepower and torque. But just increasing airflow without ensuring adequate filtration under those conditions would result in a ruined engine. K&N's solution was a filter design consisting of 4 to 6 layers of cotton gauze sandwiched between two aluminum wire screens. The cotton is then treated with a specially formulated grade of oil that causes tackiness throughout the cotton’s microscopic strands. The resulting K&N filter not only delivers increased airflow while trapping dirt particles that could harm your engine, that level of airflow is maintained even as the filter gets dirty. The layers of oiled cotton fibers in the K&N filter trap dirt particles that are smaller than the holes in the filter media. The thickness of the layers also allows the K&N filter to trap dirt and dust on many levels, trapping more dirt without decreasing airflow. Contrast this with a paper filter that only traps dirt on its surface; as the surface area becomes clogged, the airflow rate goes down.

Each K&N air filter is custom designed to fit into your existing factory air box. The K&N filter is economical because it's the last air filter you'll have to buy for your car. It can be washed and reused many times, and since you can usually drive up to 50,000 miles between servicing, you won't have to clean it very often. And every K&N filter is backed by K&N's Million Mile Limited Warranty. By the way, check the CARiD reviews and read what the customers think of K&N porducts.

K&N® is the inventor and leading innovator of reusable cotton gauze filter technology for automotive applications. The first K&N filter was conceived for racing over 40 years ago and a performance enthusiast mindset continues today throughout all levels of the company. K&N is the sales and brand leader for performance filters, including an extensive line of factory replacement filters and performance air intake kits. The company actively promotes the environmental, economical and performance advantages of long-life reusable cotton gauze filters.

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Warranty Information

Find out everything you need to know about the product warranty

K & N O/E Replacement Air Filters and Air Intake Systems purchased from Authorized Dealers are backed by a Million Mile Limited Warranty when used primarily on paved roads and on vehicles for which they were designed. If one of these products ever fails to provide complete satisfaction, K&N will replace it.

K&N Aftermarket Air Filters should be cleaned every 50,000 miles for normal highway use, more often in dusty conditions. Cleaning should be done with K&N cleaner and air filter oil (or comparable air filter cleaner and oil). Use of compressed air, or chemicals not specifically designed to clean and re-oil cotton air filters (i.e. gasoline, transmission fluid, motor oil, lightweight oil, or diesel fuel) will void the warranty. Any damaged, abused or modified K&N Air Filters will not be warranted.

Any K&N product returned to K&N will need a Return Goods Authorization number and must be sent at customers' expense along with proof of purchase.

Any defective K&N Air Filter properly returned to K&N will be replaced. K&N reserves the right to determine whether the terms of the warranty, set out above, have been properly complied with. In the event that the terms are not complied with, K&N shall be under no obligation to honor this warranty. K&N will not be responsible for any indirect, consequential, special, contingent, or other damages.

We want to make sure that when you buy a K&N Lifetime Air Filter or Air Intake System, you can be confident your vehicle's warranty will not be impacted. We also want you to feel confident that even if you experience difficulties with a dealership repair department, we will step-in and resolve the issue, so you won't have to. Therefore, K & N makes the following Pledge: K&N pledges to their customers that they will not be taken advantage of and charged for a repair due to a manufacturer warranty denial blamed on the presence of a K&N product.

Magnuson-Moss Warranty Act:
Legally, a vehicle manufacturer cannot void the warranty on a vehicle due to an aftermarket part unless they can prove that the aftermarket part caused or contributed to the failure in the vehicle (per the Magnuson Moss Warranty Act (15 U.S.C. 2302(C)) Learn More

Vehicle Fitment

This part is compatible with 125 vehicle(s)
Year Make Model Fitment Notes:
2015 Mercedes G550
2014 Mercedes G500 / G550
2013 Mercedes G550
2013 Mercedes G500
  • 5.5L
2013 Mercedes S400
2012 Mercedes C300
2012 Mercedes G500 / G550
2012 Mercedes GL450 / GL500 / GL550
2012 Mercedes GLK350
2012 Mercedes S400
2012 Mercedes SL550
2011 Mercedes C Class
  • 3.0L
2011 Mercedes C350
2011 Mercedes CL500
  • V8
2011 Mercedes CLS550
2011 Mercedes E550
2011 Mercedes E350
  • 3.5L
2011 Mercedes G500 / G550
2011 Mercedes GL450 / GL500 / GL550
2011 Mercedes GLK class
  • 3.0L
2011 Mercedes GLK350
2011 Mercedes ML550
2011 Mercedes ML350
  • 3.5L
2011 Mercedes R Class
  • 3.5L
2011 Mercedes S400
2011 Mercedes S500
  • V8
2011 Mercedes SL500 / SL550
  • V8
2011 Mercedes SLK300 / SLK350
2010 Mercedes C Class
  • 3.0L
2010 Mercedes C350
2010 Mercedes CL500 / CL550
  • V8
2010 Mercedes CLS550
2010 Mercedes E350 / E550
2010 Mercedes G500 / G55 AMG
  • 5.5L
2010 Mercedes GL450 / GL500 / GL550
2010 Mercedes GLK class
2010 Mercedes ML550
2010 Mercedes ML350
  • 3.5L
2010 Mercedes R Class
  • 3.5L
2010 Mercedes S400
2010 Mercedes S500 / S550
  • V8
2010 Mercedes SL500
  • V8
2010 Mercedes SLK300 / SLK350
2010 Mercedes SLK Class
  • 5.5L
2009 Mercedes C300 / C350
2009 Mercedes CL500 / CL550
2009 Mercedes CLK350 / CLK550
2009 Mercedes CLS550
2009 Mercedes E350 / E500 / E550
2009 Mercedes G500 / G55 AMG
  • 5.5L
2009 Mercedes GL Class
  • 4.6L / 5.5L
2009 Mercedes GLK280 / GLK350
2009 Mercedes ML350 / ML500 / ML550
2009 Mercedes R350
2009 Mercedes S500 / S550
2009 Mercedes SL500 / SL550
2009 Mercedes SLK Class
  • 3.0L / 3.5L / 5.5L
2008 Mercedes C230 / C280 / C300 / C350
2008 Mercedes CL500 / CL550
2008 Mercedes CLK350 / CLK500 / CLK550
2008 Mercedes CLS350 / CLS500
2008 Mercedes E350 / E550
2008 Mercedes G Class
  • 5.5L
2008 Mercedes G500
2008 Mercedes GL Class
  • 4.6L / 5.5L
2008 Mercedes ML350 / ML550
2008 Mercedes R350 / R500
2008 Mercedes S500 / S550
2008 Mercedes SL500 / SL55 AMG / SL550
  • 5.5L
2008 Mercedes SLK Class
  • 3.0L / 3.5L / 5.5L
2007 Mercedes C230 / C280 / C350
2007 Mercedes CL500 / CL550
2007 Mercedes CLK280 / CLK350 / CLK500
2007 Mercedes CLS350 / CLS500 / CLS550
2007 Mercedes E350 / E550
2007 Mercedes G Class
2007 Mercedes GL Class
  • 4.6L
2007 Mercedes M Class
  • 3498 CC / 4966 CC / 4973 CC
2007 Mercedes R350 / R500
2007 Mercedes S500 / S550
2007 Mercedes SL500 / SL55 AMG / SL550
  • 5.5L
2007 Mercedes SLK Class
  • 3.0L / 3.5L / 5.5L
2006 Mercedes C Class
  • 2.5L / 3.0L / 3.5L / 5.5L
2006 Mercedes CL500 / CL55 AMG
2006 Mercedes CLK Class
2006 Mercedes CLS Class
  • 5.0L / 5.5L
2006 Mercedes E class
  • 3.5L / 5.0L / 5.5L
2006 Mercedes G Class
2006 Mercedes M Class
  • 3.5L
2006 Mercedes M Class
  • 5.0L
2006 Mercedes R350 / R500
2006 Mercedes S350 / S430 / S500
2006 Mercedes SL500
2006 Mercedes SL55 AMG
  • 5.5L
2006 Mercedes SLK Class
  • 3.0L / 3.5L / 5.5L
2005 Mercedes C Class
  • 2.6L / 3.2L / 5.5L
2005 Mercedes CL500 / CL55 AMG
2005 Mercedes CLK320 / CLK500 / CLK55 AMG
2005 Mercedes CLS Class
2005 Mercedes E class
  • V6
2005 Mercedes E class
  • 5.0L / 5.5L
2005 Mercedes G Class
2005 Mercedes ML500
  • 3.82" Engine Bore
  • Fits Models Manufactured after July.
2005 Mercedes S Class
  • 4.3L / 5.0L / 5.4L
2005 Mercedes SL500
2005 Mercedes SL55 AMG
  • 5.5L
2005 Mercedes SLK Class
  • 3.5L / 5.5L
2004 Mercedes C240 / C320
2004 Mercedes CL500
2004 Mercedes CL55 AMG
  • 5.5L
2004 Mercedes CLK Class
  • 3.2L / 5.0L / 5.5L
2004 Mercedes E class
  • 3.2L / 5.0L / 5.5L
2004 Mercedes G500
2004 Mercedes S430 / S500 / S55 AMG
2004 Mercedes SL500
2004 Mercedes SL55 AMG
  • 5.5L
2003 Mercedes C240 / C320
2003 Mercedes CL500
2003 Mercedes CLK Class
  • Convertible 5.0L
2003 Mercedes CLK Class
  • Coupe 3.2L / 5.0L / 5.5L
2003 Mercedes E class
  • Sedan 3.2L / 5.0L / 5.5L
2003 Mercedes G500
2003 Mercedes S430 / S500 / S55 AMG
2003 Mercedes SL500
2003 Mercedes SL55 AMG
  • 5.5L
2002 Mercedes C240 / C320
2002 Mercedes CL500
2002 Mercedes E500
2002 Mercedes E320
  • S211
2002 Mercedes S430 / S500
2002 Mercedes SL500
2001 Mercedes C240 / C320
2001 Mercedes CL500
2001 Mercedes G500
2001 Mercedes S430 / S500
2001 Mercedes SL500
  • Non-US Built 306 BHP
2000 Mercedes CL500
2000 Mercedes G Class
2000 Mercedes S Class
2000 Mercedes SL500
  • Non-US Built 306 BHP
1999 Mercedes CL Class
  • 3.78" Engine Bore
1999 Mercedes G Class
1999 Mercedes S430
1999 Mercedes SL500
  • Non-US Built 306 BHP
1998 Mercedes S500
  • Non-US Built 306 BHP

Product Reviews


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K&N® - 33 Series Panel Air Filter
K&N® 33-2181 - 33 Series Panel Air Filter
Average Rating: 4.5 of 5
4.5 of 5
Great Filter for Any Engine
K&N® - 33 Series Panel Air Filter
I purchase these filters on all of my vehicles (past and current). I had lots of gas savings on my Toyota Highlander 2005, about 60 miles per tank more with K&N, but with 2008 model I didn't have any difference. But the ease of going up to speed was better with K&N in it. On the current Mercedes ML350 I felt a good change in acceleration as well, haven't tested MPG yet.
APosted by (Jacksonville, FL) /
2010 Mercedes M Class
Was this review helpful for you? Yes2  people found this review helpful.
K&N® - 33 Series Panel Air FilterK&N® 33-2181 - 33 Series Panel Air Filter    $47.99
4.51 review
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