K&N Engineering 81-0812 Air Oil Separator for 2020–2023 GM 6.6L HD Trucks

The K&N Air Oil Separator protects the engine and intake tract from blowby by capturing the oil in our industry leading high capacity reservoir. This helps prevent power loss and possible engine damage caused by blowby. The K&N Air Oil Separator is quick and easy to install in about 30 minutes with basic tools and uses factory-style hose connections to quickly snap on and off. The oil separator replaces the factory line from the crank case allowing the oil separator to be mounted to a coinvent location in your engine bay. No tools are needed to check and empty the oil collector reservoir. Each unit is engineered specifically for your vehicle and is backed by our No-Hassle Lifetime Limited Warranty. The K&N Air Oil Separator protects the engine and intake tract from blowby by capturing the oil in our industry leading high capacity reservoir.

• No-Hassle Lifetime Limited Warranty

The K&N Engineering 81-0812 Air Oil Separator is designed for select 2020–2023 Chevrolet Silverado 2500 HD, Chevrolet Silverado 3500 HD, GMC Sierra 2500 HD, and GMC Sierra 3500 HD trucks equipped with the 6.6L engine. It helps protect the engine and intake tract from crankcase blowby by capturing oil vapor and contaminants before they can circulate through the intake system. This can help reduce intake deposits, support consistent engine performance, and minimize potential power loss associated with blowby.

Engineered specifically for compatible GM heavy-duty applications, the K&N 81-0812 replaces the factory crankcase line and can be mounted in a convenient location within the engine bay. Factory-style hose connections allow the separator to snap into place quickly, while installation typically takes about 30 minutes using basic hand tools. The high-capacity reservoir is designed for efficient collection, and the collector can be checked and emptied without tools. The unit is backed by K&N Engineering’s No-Hassle Lifetime Limited Warranty.

Key Product Specifications & Technical Data

• Brand: K&N Engineering
• Part Number: 81-0812
• Product Type: Air oil separator catch can
• Vehicle Application: Select GM heavy-duty trucks
• Engine Application: 6.6L gasoline or diesel application as specified by vehicle fitment
• Installation: Direct replacement of the factory crankcase line
• Connections: Factory-style quick-connect hose fittings
• Warranty: No-Hassle Lifetime Limited Warranty

What’s Included

One K&N Engineering 81-0812 Air Oil Separator with vehicle-specific installation components. Verify vehicle and engine compatibility before installation. This product is not CARB approved and may not be legal for use on emissions-controlled vehicles in certain jurisdictions.

Features:

• Blowby Protection: Captures oil vapor and contaminants to help protect the engine and intake tract.
• High-Capacity Reservoir: Collects separated oil and contaminants while helping reduce intake system deposits.
• Vehicle-Specific Design: Engineered for select 2020–2023 Chevrolet Silverado and GMC Sierra 2500 HD and 3500 HD applications.
• Quick Installation and Service: Uses factory-style hose connections, installs in about 30 minutes with basic tools, and allows tool-free reservoir inspection and emptying.

Fitments:
2020 Chevrolet Silverado 2500 HD Custom
2020 Chevrolet Silverado 2500 HD High Country
2020 Chevrolet Silverado 2500 HD LT
2020 Chevrolet Silverado 2500 HD LTZ
2020 Chevrolet Silverado 2500 HD WT
2020 Chevrolet Silverado 3500 HD High Country
2020 Chevrolet Silverado 3500 HD LT
2020 Chevrolet Silverado 3500 HD LTZ
2020 Chevrolet Silverado 3500 HD WT
2020 GMC Sierra 2500 HD AT4
2020 GMC Sierra 2500 HD Base
2020 GMC Sierra 2500 HD Denali
2020 GMC Sierra 2500 HD SLE
2020 GMC Sierra 2500 HD SLT
2020 GMC Sierra 3500 HD AT4
2020 GMC Sierra 3500 HD Base
2020 GMC Sierra 3500 HD Denali
2020 GMC Sierra 3500 HD SLE
2020 GMC Sierra 3500 HD SLT
2021 Chevrolet Silverado 2500 HD Custom
2021 Chevrolet Silverado 2500 HD High Country
2021 Chevrolet Silverado 2500 HD LT
2021 Chevrolet Silverado 2500 HD LTZ
2021 Chevrolet Silverado 2500 HD WT
2021 Chevrolet Silverado 3500 HD High Country
2021 Chevrolet Silverado 3500 HD LT
2021 Chevrolet Silverado 3500 HD LTZ
2021 Chevrolet Silverado 3500 HD WT
2021 GMC Sierra 2500 HD AT4
2021 GMC Sierra 2500 HD Base
2021 GMC Sierra 2500 HD Denali
2021 GMC Sierra 2500 HD SLE
2021 GMC Sierra 2500 HD SLT
2021 GMC Sierra 3500 HD AT4
2021 GMC Sierra 3500 HD Base
2021 GMC Sierra 3500 HD Denali
2021 GMC Sierra 3500 HD SLE
2021 GMC Sierra 3500 HD SLT
2022 Chevrolet Silverado 2500 HD Custom
2022 Chevrolet Silverado 2500 HD High Country
2022 Chevrolet Silverado 2500 HD LT
2022 Chevrolet Silverado 2500 HD LTZ
2022 Chevrolet Silverado 2500 HD WT
2022 Chevrolet Silverado 3500 HD High Country
2022 Chevrolet Silverado 3500 HD LT
2022 Chevrolet Silverado 3500 HD LTZ
2022 Chevrolet Silverado 3500 HD WT
2022 GMC Sierra 2500 HD AT4
2022 GMC Sierra 2500 HD Base
2022 GMC Sierra 2500 HD Denali
2022 GMC Sierra 2500 HD SLE
2022 GMC Sierra 2500 HD SLT
2022 GMC Sierra 3500 HD AT4
2022 GMC Sierra 3500 HD Base
2022 GMC Sierra 3500 HD Denali
2022 GMC Sierra 3500 HD SLE
2022 GMC Sierra 3500 HD SLT
2023 Chevrolet Silverado 2500 HD Custom
2023 Chevrolet Silverado 2500 HD High Country
2023 Chevrolet Silverado 2500 HD LT
2023 Chevrolet Silverado 2500 HD LTZ
2023 Chevrolet Silverado 2500 HD WT
2023 Chevrolet Silverado 3500 HD High Country
2023 Chevrolet Silverado 3500 HD LT
2023 Chevrolet Silverado 3500 HD LTZ
2023 Chevrolet Silverado 3500 HD WT
2023 GMC Sierra 2500 HD AT4
2023 GMC Sierra 2500 HD Denali
2023 GMC Sierra 2500 HD Pro
2023 GMC Sierra 2500 HD SLE
2023 GMC Sierra 2500 HD SLT
2023 GMC Sierra 3500 HD AT4
2023 GMC Sierra 3500 HD Denali
2023 GMC Sierra 3500 HD Pro
2023 GMC Sierra 3500 HD SLE
2023 GMC Sierra 3500 HD SLT
2024 Chevrolet Silverado 2500 HD Custom
2024 Chevrolet Silverado 2500 HD High Country
2024 Chevrolet Silverado 2500 HD LT
2024 Chevrolet Silverado 2500 HD LTZ
2024 Chevrolet Silverado 2500 HD WT
2024 Chevrolet Silverado 2500 HD ZR2
2024 Chevrolet Silverado 3500 HD High Country
2024 Chevrolet Silverado 3500 HD LT
2024 Chevrolet Silverado 3500 HD LTZ
2024 Chevrolet Silverado 3500 HD WT
2024 GMC Sierra 2500 HD AT4
2024 GMC Sierra 2500 HD AT4X
2024 GMC Sierra 2500 HD Denali
2024 GMC Sierra 2500 HD Pro
2024 GMC Sierra 2500 HD SLE
2024 GMC Sierra 2500 HD SLT
2024 GMC Sierra 3500 HD AT4
2024 GMC Sierra 3500 HD Denali
2024 GMC Sierra 3500 HD Pro
2024 GMC Sierra 3500 HD SLE
2024 GMC Sierra 3500 HD SLT
2025 Chevrolet Silverado 2500 HD Custom
2025 Chevrolet Silverado 2500 HD High Country
2025 Chevrolet Silverado 2500 HD LT
2025 Chevrolet Silverado 2500 HD LTZ
2025 Chevrolet Silverado 2500 HD WT
2025 Chevrolet Silverado 2500 HD ZR2
2025 Chevrolet Silverado 3500 HD High Country
2025 Chevrolet Silverado 3500 HD LT
2025 Chevrolet Silverado 3500 HD LTZ
2025 Chevrolet Silverado 3500 HD WT
2025 GMC Sierra 2500 HD AT4
2025 GMC Sierra 2500 HD AT4X
2025 GMC Sierra 2500 HD Denali
2025 GMC Sierra 2500 HD Pro
2025 GMC Sierra 2500 HD SLE
2025 GMC Sierra 2500 HD SLT
2025 GMC Sierra 3500 HD AT4
2025 GMC Sierra 3500 HD Denali
2025 GMC Sierra 3500 HD Pro
2025 GMC Sierra 3500 HD SLE
2025 GMC Sierra 3500 HD SLT

Air Freight Prohibited: false
Not Carb Approved: true
Ltl Freight Required: false
Prop 65: Y
Part Type: automotive
Epa: N/A
Carb Acknowledgement Required: false
Regular Stock: t
Units Per Sku: 1