Dorman 4WD Actuator Vacuum Check Valve 926-390 for Ford/Lincoln 2015-2018 — Direct-Fit, One-Way Vacuum Seal

The Dorman 926-390 4WD actuator vacuum check valve is a direct-fit replacement designed to restore correct vacuum control for compatible Ford and Lincoln four-wheel-drive systems.

This replacement vacuum check valve is built to match the original component’s fit and function so your 4WD vacuum circuit can maintain the pressure needed for actuator operation. Engineered from durable materials and backed by Dorman’s long automotive experience, the 926-390 is intended as a straightforward fix when the factory valve fails or leaks. Before ordering, confirm the exact fit for your vehicle using your make, model and trim in the garage tool.

How does this valve restore proper 4WD vacuum performance?

The check valve prevents vacuum loss by allowing one-way flow and sealing against backflow when the system is not under vacuum. Replacing a worn or cracked valve helps the actuator receive stable vacuum pressure so the 4WD engagement parts can operate more consistently.

• One-way vacuum control to prevent unintended pressure loss.
• Precisely molded ports to match OEM routing and tubing connectors.
• Seals tightly to reduce leaks that cause actuator hesitation.

Which vehicles is the Dorman 926-390 compatible with?

This part is produced for specific Ford and Lincoln model years that used the same vacuum check valve design. Compatibility is model- and trim-dependent, so verify with your vehicle information before purchasing.

• Ford F-150 — model years 2015, 2016, 2017 and 2018.
• Ford Expedition — 2018 model year support.
• Lincoln Navigator — compatible with 2018 vehicles using the same valve layout.

What are the practical benefits of choosing this Dorman replacement?

Installing the 926-390 can eliminate vacuum leaks, improve actuator response, and reduce 4WD engagement issues caused by a failed check valve. It’s manufactured to match original dimensions so installation is typically straightforward.

• Direct replacement design for easy installation without modification.
• Durable material construction for longer service life under engine-bay conditions.
• Backed by Dorman’s product support and decades of aftermarket experience.

Can I install the check valve myself, and what should I check during installation?

Many owners and technicians can replace this valve with basic hand tools and careful hose removal. Ensure vacuum lines are routed the same way, inspect hoses for cracks, and test the 4WD engagement after installation.

• Use pliers to release hose clamps and replace only the damaged valve first.
• Confirm the arrow or flow direction on the valve matches original orientation.
• Check connected hoses and actuators for wear to prevent repeat failure.

Who is this for: The Dorman 926-390 is intended for owners and mechanics working on Ford F-150 (2015–2018), Ford Expedition (2018) and Lincoln Navigator (2018) vehicles who need a reliable, OEM-style replacement vacuum check valve. It’s a practical option for anyone troubleshooting intermittent 4WD engagement, vacuum leaks in the actuator circuit, or replacing a visibly damaged valve. Make sure to confirm fitment with your exact trim and vehicle year before ordering to ensure proper compatibility.