Walker 350-34993 Oxygen Sensor - Downstream Left or Downstream Right

Walker 350-34993 Oxygen Sensor for Ford and Lincoln

Walker Products 350-34993 is a heated, specific-fit oxygen sensor engineered as an OE-style replacement for downstream applications. It is built for the 2015-2018 Lincoln Navigator and 2015-2017 Ford Expedition in downstream left and downstream right positions, helping the ECU receive the exhaust feedback it expects.

Key Features

• Specific-fit oxygen sensor for targeted downstream placement
• Heated sensor design for faster operating response
• 4-wire configuration with 20-gauge wiring
• 13.18 in. wiring harness length and 15.74 in. overall length
• 18.0 mm thread diameter with threaded mounting
• Female connector with radiused polygon shape
• Walker Products Aftermarket line for engine management and oxygen sensor replacement

Detailed Description

Walker Products Aftermarket focuses on engine management and oxygen/air-fuel sensors built for direct replacement use across many vehicle platforms. Part number 350-34993 is designed for the downstream oxygen sensor location on select Ford Expedition and Lincoln Navigator models, including downstream left and downstream right positions. For shoppers searching for a 2015-2017 Ford Expedition downstream oxygen sensor or a 2015-2018 Lincoln Navigator downstream O2 sensor, this application-specific part provides the correct fitment and connector style for the listed vehicles.

As an OE-replacement sensor, this Walker oxygen sensor is intended to deliver the diagnostic feedback the ECU uses to monitor exhaust performance. The heated design supports sensor operation after startup, while the threaded mounting and 18.0 mm thread diameter match the specified exhaust bung application. Part number 350-34993 is also a practical match for buyers comparing Walker 350-34993 against other downstream oxygen sensor listings for Ford Expedition and Lincoln Navigator service work.

What It Helps Address

• Check engine light related to downstream oxygen sensor faults
• Poor fuel economy caused by inaccurate exhaust feedback
• Elevated exhaust emissions from a failing sensor
• Rough engine operation tied to incorrect ECU input
• Damaged sensor wiring, connector, or harness-related diagnostic issues

Installation Notes and Tips

Verify the vehicle’s fault codes and confirm the sensor position before replacement. Inspect the sensor wiring harness and connector for heat damage, abrasion, or corrosion, since physical damage can shorten service life. Confirm the downstream left or downstream right location on the Ford Expedition or Lincoln Navigator before ordering Walker 350-34993.

Quality Assurance

Walker Products states that its engine management sensors are developed as OE replacement parts and the company is ISO 9001/TS 16949 certified. Since 1946, Walker Products has supplied engine management and fuel system components for automotive applications.