Bosch 13701 Oxygen Sensor - Downstream Left

Bosch Validated Oxygen Sensor 13701

Bosch Validated Oxygen Sensor 13701 is a narrow-band heated O2 sensor built for precise air-fuel-ratio feedback to the ECU. It supports stable combustion control and emissions management in confirmed applications such as the 2001-2002 Chevrolet Silverado 2500 HD and 2001-2002 GMC Sierra 2500 HD.

Key Features

• Specific-fit oxygen sensor for direct application matching
• Narrow-band heated design for faster closed-loop operation
• 4-wire configuration with blade terminals and trapezoid connector
• Threaded mounting with 18 mm thread diameter and 22 mm hex size
• Metal housing with high-temperature-resistant construction
• Wiring harness included for service replacement
• Fits downstream left positions in listed Chevrolet and GMC applications

Product Details

Bosch 13701 is part of the Bosch Validated Oxygen Sensor line, a product family developed from Bosch OE oxygen sensor engineering and refined through decades of emissions-system development. This narrow-band heated sensor uses advanced ceramic elements and controlled heater performance to deliver accurate lambda feedback under changing exhaust temperatures and vibration loads. It is a direct replacement choice for downstream left service on 2001-2002 Chevrolet Silverado 2500 HD, Silverado 3500, Suburban 2500, and 2002 Chevrolet Avalanche 2500, as well as 2001-2002 GMC Sierra 2500 HD, Sierra 3500, and Yukon XL 2500. This part cross-references GM 12565415 for the same application.

What It Helps Address

• Check engine light related to oxygen sensor performance
• Incorrect air-fuel ratio feedback to the ECU
• Slow closed-loop response after exhaust warm-up
• Rough combustion control caused by aging sensor output
• Emissions test failures tied to a worn downstream sensor

Installation Notes and Tips

Install Bosch 13701 in the downstream left location only where listed fitment confirms application match. Verify the 18 mm thread size, 22 mm hex, 4-wire connector layout, and trapezoid plug before installation. Inspect the exhaust bung threads and wiring routing before tightening the sensor to avoid connector strain or thread damage.

Quality Assurance

Bosch backs this oxygen sensor line with more than five decades of OE development experience. The Bosch Validated Oxygen Sensor 13701 is built to OE-proven standards for accurate signal control and durable service in demanding exhaust environments.