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

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Availability: In Stock.
Fulfilled by Amazon

Arrives Wednesday, Oct 22
Order within 21 hours and 56 seconds
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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


Automotive Fit Type: Vehicle Specific Fit


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: Wednesday, Oct 22

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


  • ⭐️⭐️⭐️⭐️⭐️ 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

  • My Go-To Engine Air Filter for My 2023 Mazda CX-5
Size: MT-259 1-Pack
I bought this air filter after reading the reviews, and I was not disappointed. The filter fit my 2023 Mazda CX-5 perfectly, and I haven't noticed any decrease in vehicle performance or gas mileage. The quality is as good as OEM filters for anyone looking to avoid inflated dealership and auto shop engine filter replacement costs. ... show more
Reviewed in the United States on September 14, 2025 by J. Hall

  • Good fit, sturdy build, easy install; time will tell on performance.
Size: MT-683 1-Pack
I ordered this filter for my 2010 Toyota Tacoma Double Cab V6 to replace an old worn K&N Filter. The value for the money is good, and if you do a side by side value and comparison between the K&N filter and cost of cleaning vs just purchasing a new filter over time, the savings are negligible. I prefer to purchase new filters when needed. On to this filter. The Spearhead filter looks a bit more robust and sturdy than the typical aftermarket filter you can purchase from Pep Boys or Auto Zone and the cost is a few dollars cheaper than buying at a brick and mortar store. The filter itself looks good and claims to remove 99.9% of particulates, but only time will tell. The build quality of the filter is sturdy and I have no qualms about the quality, etc of the filter. The filter fit perfectly in my Tacoma's engine air compartment; there were no problems with fit or closing the seal. The performance of the vehicle is great, no issues or any engine problems. As far as claims of increased power and improvement in acceleration, I have seen little to no difference with this filter. K&N's and any other aftermarket product's claims including Spearhead's are subjective until I see some way to measure this vs a traditional OEM filter. To be honest, all these claims seem to me to be marketing hype, but I am not qualified to comment. Overall, I am satisfied with this purchase and will re-evaluate it in a year (my truck is low mileage) or when the mileage hits and is due for a change. I am satisfied with this purchase, but only time will tell. I will buy again if I have no issues. ... show more
Reviewed in the United States on December 26, 2019 by DJB

  • As advertised
Size: MT-465 1-Pack
Order came quickly, was the right filter for my car, and cheaper than an auto parts store
Reviewed in the United States on August 18, 2025 by Michael Tusa

  • Perfect fit
Size: MT-050 1-Pack
It was easy to find the correct filter for my car. Fits perfectly and working well.
Reviewed in the United States on September 15, 2025 by Howling

  • Great Filters! Some car models require you to gently squeeze filter sides as you inch it in.
Size: MT-290 1-Pack
Spearhead engine air filters are awesome and so are the cabin filters. Been using them for years. I have an 18 Accord, 19 Odyssey, and a 21 Passport. The cabin filters slide right in for the Accord and Passport. It's a tight fit for the Odyssey but you can inch it in by squeezing the sides of the filter as you push. Pulling out will be a bit rough a year later since it's pretty much squeezed. Note, the accord is a different size filter from the Odyssey and Passport which are the same. Never had size issues for the engine filters. I replace the engine filters annually after pollen season but can go longer. ... show more
Reviewed in the United States on April 19, 2025 by daschubs

  • 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

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