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AEM C.A.S. 17-18 Subaru Legacy H4-2.5L F/I - 21-856C
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AEM Induction
SKU:
AEM21-856C
|
- UPC:
- 024844369154
- Availability:
- Regularly stocked product
$419.99
Other AEM Induction kits for this car
Fits these vehicles
- 2017-2018 Subaru Legacy2.5i, 2.5i Limited, 2.5i Premium, 2.5i Sport
- 2017 Subaru Legacy2.5i Touring
- 2017-2018 Subaru Legacy3.6R Limited
Part details
- Part number
- AEM21-856C
- Manufacturer part number
- 21-856C
- UPC
- 024844369154
- Brand
- AEM Induction
- CARB
- Not for sale or use in California (no CARB EO)
- Prop 65
- ⚠️ WARNING: This product can expose you to chemicals which are known to the State of California to cause cancer. For more information, go to www.P65Warnings.ca.gov
- Instructions
- Installation instructions (PDF)
- Material
- Aluminum
Installation guide (from AEM Induction)
Hosted by AEM Induction. Follow the maker's instructions and torque specs.
- Box size:
- 13.20 × 10.60 × 35.30 (in)
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AEM C.A.S. 17-18 Subaru Legacy H4-2.5L F/I - 21-856C
$419.99
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-
Only 5 left in stock
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Only 2 left in stock
AEM 2018 Subaru WRX STI 2.5L H4 F/I Cold Air Intake System - Wrinkle Red - 21-836WR
$349.99Free Shipping
The AEM Performance Cold Air Intake System produces horsepower and torque gains by replacing your vehicle's restrictive factory air filter and air intake housing. This air intake system was designed, tuned and dyno-tested to fit specific models. Air enters the system through an oversized AEM Dryflow synthetic washable air filter for outstanding air flow, filtration and performance. The air filter is located in the original air box space and is protected by a heat shield which is designed to reduce intake air temperature and increase horsepower. The air intake tube is constructed from mandrel-bent aluminum featuring a durable gunmetal gray powder coated finish. This air intake system was developed to accommodate the engine's factory emissions control devices including the mass airflow sensor and breather tube. The tapered cylinder shaped AEM Dryflow air filter is made from an oil-free, synthetic filter media that can be used for up to 100,000 miles before cleaning is needed (depending on driving conditions). The air intake system is easy to install with commonly available tools and it is backed by AEM's Lifetime Limited Warranty. Some AEM air intakes are not legal for sale or use in California and other states adopting California emission standards, while others are 50 state legal. View the vehicle applications to determine the legal status for each vehicle.
This Part Fits:
This Part Fits:
| Year | Make | Model | Submodel |
|---|---|---|---|
| 2017-2019 | Subaru | Legacy | 2.5i |
| 2017-2019 | Subaru | Legacy | 2.5i Limited |
| 2017-2019 | Subaru | Legacy | 2.5i Premium |
| 2017-2019 | Subaru | Legacy | 2.5i Sport |
- LTL:
- N
- MPN:
- 21-856C
- Proposition 65:
- Y
- Special Order:
- N
- Clearance Item:
- N
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AEM Induction
AEM C.A.S. 17-18 Subaru Legacy H4-2.5L F/I - 21-856C
AEM C.A.S. 17-18 Subaru Legacy H4-2.5L F/I - 21-856C FAQ
It is listed for: 2017-2018 Subaru Legacy; 2017 Subaru Legacy; 2017-2018 Subaru Legacy. Pick your vehicle on this page to check your exact year and trim.
No — this part has no CARB Executive Order, so it is not for sale or use in California or on vehicles registered there.
The maker's installation guide is on this page — see Installation guide under the part details for the step-by-step and the torque figures. Work on level ground with the car properly supported, and torque every fastener to the maker's figure. If the job is beyond your tools, any shop that does this kind of work can fit it.
Most intakes work with the stock tune. When an intake changes the sensor housing size, the maker says a tune is required.
Follow the maker's service interval. Dry filters are blown out or washed; oiled filters are washed and re-oiled with the maker's kit. Over-oiling can foul the airflow sensor.
Yes. Most intakes make the induction sound louder, especially at wide throttle.
Yes. An intake is usually a bolt-on job with hand tools; the maker's guide covers the clamps and the sensor move.
A full intake kit includes its filter; a replacement filter is sold on its own. See What's in the box above.
Yes — monthly options show right under the Add to Cart button. Affirm, Klarna, PayPal Pay Later and Snap Finance are offered at checkout, and checking what you qualify for does not affect your credit score.
Install and care: cold air intake
Before you start
- Read the maker's guide for where the airflow sensor moves to.
- Have the clamps and hand tools the guide names within reach.
Do
- Seat every coupler fully and tighten the clamps evenly.
- Service the filter on the maker's interval and use the maker's cleaning kit.
Don't
- Don't over-oil an oiled filter; it fouls the airflow sensor.
- Don't run the engine with a coupler loose.