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Spearhead MPG Defense Max Thrust Engine Air Filter For All Mileage Vehicles, Fits Like OEM, Restores MPG & Acceleration (MT-997)

  • Based on 26,176 reviews
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Availability: In Stock.
Fulfilled by Amazon

Arrives Sep 6 – Sep 7
Order within 7 hours and 29 minutes
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Size: MT-997 1-Pack


Features

  • Experience an Obvious Difference: Whether you are noticing a delay in acceleration, less than average gas mileage or own a higher mileage vehicle, our Max Thrust engine air filters will provide a clear and cost effective upgrade over stock performance
  • Trap 2X Dirt vs. Standard Air Filters: Our unique Hex-D pleat design creates maximum holding capacity for trapping unwanted dirt and debris without compromising airflow like standard air filters thanks to multiple layers of progressively finer filter media that allows air to flow freely even when the filter is dirty
  • Increased Power and Mileage up to 15K Miles: Deficient airflow can cause your engine to work twice as hard to suck in the minimum amount of air it needs to perform regularly, resulting in poorer gas mileage and lower power efficiency; Max Thrust air filters are designed to give your engine a break by delivering as much clean air as it needs to perform optimally up to 15K miles
  • Do It Yourself: Replacement for Crosstrek (2016-17, does not fit Hybrid), Forester (2009-18, does not fit 2008 Forester), Impreza (2008-16, fits all trims), Legacy (2005-19), Outback (2005-19), Tribeca (2008-14), WRX (2012-21), WRX STI (2013-18, does not fit 2018 Type RA), make sure to enter your year, make and model above to check fitment; the engine air filter is an easy replacement that can save you money at the repair shop
  • Better Filter than Your Last One: We know its hard to choose from so many different brands carrying the same product; we make it easier for our customers to decide with a simple promise

Description

Compatible Model and Year List (please verify using Amazon’s ‘My Garage’) Crosstrek (2016-2017, does not fit Hybrid), Forester (2009-2018, does not fit 2008 Forester), Impreza (2008-2016, fits all trims), Legacy (2005-2019), Outback (2005-2019), Tribeca (2008-2014), WRX (2012-2021), WRX STI (2013-2018, does not fit 2018 ‘Type RA’) About Spearhead We are a family-owned operation leveraging 30 years of automotive parts sourcing for some of the largest automotive aftermarket suppliers in the United States to build a brand customers can trust to find the best products at the best prices. Cross Reference Part No.’s Spearhead: MT-997Fram: CA9997 Did you know this about engine air filters? An engine air filter will pay for itself with the money you save at the gas pump…a new engine air filter can increase your vehicle’s MPG by up to 10%.There’s no better or cheaper investment you can make to extend the life of your vehicle than regularly replacing your engine air filter every 12-15K miles. When is the ‘right’ time to replace my engine air filter? Warning/Engine Light Turns On: A light will appear on vehicles equipped with airflow sensors.Noticeably Slower Acceleration: If your vehicle is slow to accelerate or responds poorly to pedal control this can mean your engine isn't receiving enough air to perform normally.Reduced Fuel Economy: The less oxygen an engine consumes, the more fuel it will burn – causing fuel economy to go down.Up to 15K Miles or 1 Year: If you don’t remember the last time you replaced your engine air filter it’s time to change it out! Questions or Concerns? If you have any questions/concerns, message us using Amazon’s ‘contact seller’ form.

Brand: SPEARHEAD


OEM Part Number: CA9997


Shape: Square


Manufacturer: Spearhead


Manufacturer: ‎Spearhead


Brand: ‎SPEARHEAD


Item Weight: ‎8.4 ounces


Package Dimensions: ‎8.94 x 8.82 x 1.77 inches


Item model number: ‎MT-997


Manufacturer Part Number: ‎MT-997


OEM Part Number: ‎CA9997


Date First Available: June 25, 2019


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sep 6 – Sep 7

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • As good as O.E.M. for a lot less.
Size: MT-295 1-Pack
Fit my 2021 Subaru Crosstrek Limited like it was made for it. Easy peazy all of about 5 minutes and that was with vacuuming out the air box. Seemed as good of quality as OEM.
Reviewed in the United States on August 10, 2025 by Ermster

  • ⭐️⭐️⭐️⭐️⭐️ Excellent Air Filter – Restored MPG & Acceleration!
Size: MT-450 1-Pack
This Spearhead MPG Defense Max Thrust Engine Air Filter (MT-450) is a fantastic upgrade over stock filters! Installation was super easy, and the OEM fit was perfect for my 2015 Nissan Altima 2.5L—it dropped right in with no issues. Since replacing my old filter, I’ve noticed improved throttle response and smoother engine operation. My gas mileage even went up by 2 MPG, which is a great bonus! The Hex-D pleat design truly traps more dirt while maintaining strong airflow. For just $13.99, the quality and performance exceed expectations—better than higher-priced options. If you want a simple, cost-effective way to enhance fuel efficiency and acceleration, this is a must-buy! Highly recommend! 🚗🔧✅ ... show more
Reviewed in the United States on May 29, 2025 by El Boomer

  • Good product
Size: MT-061 1-Pack
Easy to install. Good quality and good price. I would recommend.
Reviewed in the United States on August 11, 2025 by Tony Guo

  • Good replacement filter
Size: MT-470 1-Pack
I bought this filter for my Hyundai Elantra 2010. The package arrived on time. The installation was quite easy. It was a good fit.
Reviewed in the United States on July 13, 2025 by Handyman

  • Replacement was a breeze!
Size: MT-997 1-Pack
Perfect drop-in fit for my 2017 Accord. It looks and feels the same as the genuine Honda filter it replaced; the thickness, weight, and number of pleats were identical! Great quality - I will use for my other vehicle as well.
Reviewed in the United States on June 10, 2025 by RAH

  • Excellent quality
Size: MT-600 1-Pack
Excellent quality, perfect fit. I use this brand as well for my cabin filter application.
Reviewed in the United States on June 24, 2025 by J.S

  • Great performance and mpg from a low cost filter. A+
Size: MT-755 1-Pack
Excellent performance. Stopped using K&N because the oil would dirty up the MAF sensor. Tried this filter and haven't had to clean the sensor since, I'll still clean it as a precautionary maintenance but not because I have to. Fuel mileage is at 22.5 in the Jeep instead of the 23mpg for the K&N but this Max Thrust filters out more dirt. Performance is an easy A+, it accelerates better. It's inexpensive and easy to do, I change it every 6 months. ... show more
Reviewed in the United States on March 19, 2025 by ChimChim

  • Cheap DIY
Size: MT-262 1-Pack
Fits my 2021 ford expedition Max. Watched a YouTube tutorial it was easy to change took me about 5 minutes. Saves you so much time and money! Wil be ordering again.
Reviewed in the United States on June 14, 2025 by Pamboo

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