K&N 02-09 Cadillac / 99-09 Chevy/GMC PickUp Drop In Air Filter - 33-2135 - KNN33-2135

The K&N 33-2135 Drop-In Air Filter is a high-flow, washable replacement air filter purpose-built for 2002–2009 Cadillac pickups and 1999–2009 Chevrolet and GMC pickup trucks. Engineered to slip directly into your factory airbox with zero modifications, the 33-2135 is one of the most popular performance air filter upgrades for GMT800- and GMT900-era GM truck owners who want more airflow without giving up the convenience of a stock-style installation.

Key Features & Benefits

• Drop-In Fit, No Modifications Required: The 33-2135 is custom-designed to fit your existing factory airbox, so installation is as simple as swapping out the old paper filter — no cutting, clamping, or re-routing required.
• Washable & Reusable: Unlike disposable paper filters that go in the trash every 12,000–15,000 miles, the K&N 33-2135 is designed to be cleaned, re-oiled, and reinstalled — dramatically reducing long-term filtration costs.
• Engineered for Increased Airflow: K&N's high-flow filter media is designed to allow more air to reach the engine compared to a standard OEM paper filter, which K&N states is intended to increase horsepower and acceleration.
• Designed to Last the Life of Your Vehicle: K&N engineers this filter to hold up for the entire lifespan of your truck, making it a one-time purchase rather than a recurring maintenance expense.
• 10-Year / Million Mile Limited Warranty: K&N backs the 33-2135 with their industry-recognized 10-Year/Million Mile Limited Warranty, reflecting confidence in the filter's long-term durability.
• Proposition 65 Compliant: Noted as a Proposition 65 product — relevant for buyers in California.

Specifications

• Brand: K&N Engineering
• Part Number (MPN): 33-2135
• SKU: KNN33-2135
• UPC: 024844071897
• Filter Type: Drop-In / Panel (fits factory airbox)
• Filter Design: Washable and reusable high-flow filter
• Warranty: K&N 10-Year / Million Mile Limited Warranty
• Proposition 65: Yes

Fitment

The K&N 33-2135 is confirmed to fit the following vehicles:

• Cadillac Pickup: 2002–2009
• Chevrolet Pickup: 1999–2009
• GMC Pickup: 1999–2009

This covers a wide range of GMT800 and GMT900 platform GM full-size trucks, including many Silverado 1500, Silverado 2500HD, Sierra 1500, Sierra 2500HD, and Escalade EXT variants within those model years. If you are unsure whether this filter is the correct fit for your specific engine or trim level, contact the ThreePiece.us fitment team before ordering — they can verify compatibility for your exact build.

Why Buy from ThreePiece.us

• Free Shipping: Every order ships free — no minimum, no hidden fees.
• Affirm Financing: Spread your purchase over time with flexible financing through Affirm, available at checkout.
• Expert Fitment Support: ThreePiece.us has served 10,000+ customers and has a dedicated fitment support team ready to verify that parts are correct for your specific truck. Reach out by phone at 813-535-5801 or by email before ordering if you have any questions.
• Regularly Stocked: The K&N 33-2135 is listed as a regularly stocked product, meaning you won't face the extended lead times associated with special-order items.

Frequently Asked Questions

Q: Will the K&N 33-2135 fit my specific Chevy Silverado or GMC Sierra engine?
A: The 33-2135 is confirmed to fit 1999–2009 Chevrolet and GMC pickups and 2002–2009 Cadillac pickups. Because several different engines were offered across these model years and trims, we recommend contacting our fitment team at 813-535-5801 to confirm compatibility with your specific engine before ordering.

Q: Do I need any special tools or modifications to install the 33-2135?
A: No. The 33-2135 is a direct drop-in replacement designed to fit your factory airbox exactly. No cutting, drilling, or additional hardware is required — installation is a straightforward filter swap.

Q: Is this filter truly reusable, and how long will it last?
A: Yes. K&N engineers the 33-2135 to be washable and reusable, and they state it is designed to last for the entire lifespan of your vehicle. It is backed by K&N's 10-Year/Million Mile Limited Warranty.

Q: Is this a special-order item, or is it in stock?
A: The K&N 33-2135 is listed as a regularly stocked product at ThreePiece.us, so typical special-order lead times do not apply.