$51.99 USD
MSRP $80.09 35.1% Off
Will ship as soon as it becomes available. Not In Stock
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K&N 33-2157 Air Filter

Replacement Filters > Replacement Air Filter
  • Designed to boost horsepower and rate of acceleration
  • Can be cleaned and used again
  • High air flow with exceptional filtration
  • Lasts up to 50,000 miles before cleaning is required depending on driving conditions
  • Works with original equipment manufacturer vehicle electronics
  • Emissions legal in all 50 US states
  • Will NOT void vehicle warranty
  • Million Mile Limited Warranty®
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.

[More Information on K&N Replacement Air Filters]

Product Specifications

Air Filter ShapePanel
Filter MaterialCotton Gauze
Filter Re-Oiling Amount1 oz (30 ml)
Height1.125 in (29 mm)
Outside Length10.25 in (260 mm)
Outside Width6.5 in (165 mm)
Package Contents1 Air Filter
Package Quantity1
Product Box Height13.56 in (345 mm)
Product Box Length7.72 in (196 mm)
Product Box Width1.75 in (44 mm)
Product StylePanel Air Filter
Weight0.8 lb (0.4 kg)

Customer Feedback

I recently had to retire my 1990 Mazda Protege GT (1.8l, 4cyl) and bought a used 1993 Mazda 626ES with a 2.5l V6 (both with manual transmissions, but the 626 is a much bigger and much heavier car).  I was a bit concerned about the fuel consumption of the 2.5l having had a car with a smaller engine (27~30 mph city, 40+ mpg highway).  I bought the K&N filter to see if it could help out with squeezing a few more miles per gallon.  Presently it stands at about 25 mpg in mixed driving.  While it's early to tell, what I can tell you is that from the first time I turned over the engine, I knew that there was a difference.  

The filter in the car (when I bought it) was brand new.  I felt that the engine was a little slow on response when I pressed on the gas pedal, even when it was already revving.  I thought that this was normal as I hadn't had the car for very long.  With the K&N filter and without a doubt, the engine revs up much more freely.  It's amazing how getting more air into the engine literally breathes new life into it!  An of course, there is that little improvement in the sound of the engine as well.

Again, I'm not sure (yet) about any mileage increase, but will write back and repost after a few tanks have been used.  So far, very impressed!  The Zoom-Zoom is back!

Vancouver, Canada
I have been a fan of K&N air filters since the mid 90's.  The first filter I used was on my 87' Jeep Cherokee and it made a huge difference!  I immediately gained a 10% increase in gas mileage, faster throttle response, and a much smoother running engine.  The Straight 6 4.0 Liter engine is amazing to start with, but even better with a K&N!  I have installed half a dozen K&N filters on my friends' vehicles including a 97' GMC 1500 Truck, 98' Mazda 626, and my 01' Jeep Cherokee.  What a great product!!!

I wanted to tell you my experience with your air filter product. Recently, I watched the NHRA race in Pomona that was sponsored by your company. I saw a promo piece during that show about the K&N Filter line and was interested in the things mentioned in that story. I was talking with a friend at work the following Monday. He has a '96 Ford Thunderbird V8 with many enhancements. He told me he had been using your air filter products in his cars for a long time and showed me his slick home-made air intake system. He told me he was sold on your filter and recommended I try one. Next, I went on the 'web' to your site and learned more. I went to other sites and noticed that competitor's were saying things like, "... it's as good as a K&N," or " is very similar to a K&N." I realized that if they were comparing theirs to yours, it must make you the leader. I have a 1998 Mazda 626 V6 with 36K miles. I am very picky about the parts I use in my cars so I have been reluctant to replace parts that were not factory marked. This would be a big leap of faith for me. A few months ago I had a Mazda air filter replaced and I had them return the old one to me to see the level of contamination I was accumulating in that period. As I looked at the filter I noticed how poorly made it was. Never mind the paper filter portion, the whole thing was a sloppy piece of junk. This upset me because I was charged nearly $30 for it. So I went over to Trak Auto and looked at a few panel filters similar to the one I would need. I noticed it was a nice product. All the seams were tight and the quality was apparent. I ordered a 33-2157 (made in USA) filter and it arrived in a couple days. I picked it up and dropped it in. I have to admit, I didn't notice a major power jump but I know it's improved. The reason I know is because when I accelerated at a medium level in 'OD' gear, the car always seemed to want to down shift into 3rd immediately. It isn't doing that any more. It moves out steadily and briskly and will not downshift until I really push the pedal down. This is an improvement for me. I never felt this car should be so quick to jump down with medium pressure on the gas pedal. Now, it certainly saves gas and prevents the engine from loading up high RPM's for a routine acceleration. After driving awhile, I have noticed a bit more acceleration and more reaction at the higher end. In addition, I have realized a nice MPG jump on my combo commute (street/freeway) of 50 miles round trip. Previously, I would avg. 21 MPG if I was soft footed. Now I am getting 22.5 avg. with a heavier foot. I think I can get to 23 avg. if I go back to a soft foot. This was a KEY benefit for me. In my opinion, your product has exceeded your claims and that is rare today.

I want you to know that your support of racing on TV deserves notice ONLY if you have the products to warrant notice and I think you do. I am a supporter of auto product companies that support racing and racers. That was the 'hook' that got me to look twice at your company. But it was the product that made us friends. Keep up your research and support of the racing sports and motoring in general.


Rick Good
Anaheim, California