?2pcs Upstream & Downstream Fits 2003-2006 GMC Sierra 3500 8.1L O2 Oxygen Sensor

For 2001-02 GMC Yukon XL 2500 8.1L Oxygen O2 Sensor 02 Upstream+Downstream 2pcs

Downstream O2 Oxygen Sensor for 03~06 Chevy Silverado 2500 HD 3500 8.1L 234-4673

2pcs Upstream Downstream O2 02 Oxygen Sensor for 03-2006 GMC Yukon XL 2500 8.1L

2pcs Upstream & Downstream for 2001-02 GMC Sierra 2500 HD 8.1L O2 Oxygen Sensor

2pcs Fits 03-06 GMC Sierra 2500 HD 8.1L O2 Oxygen Sensor Upstream & Downstream

2pcs Upstream & Downstream for 2003-2006 GMC Yukon XL 2500 8.1L O2 Oxygen Sensor

2pcs Upstream & Downstream for 2001-02 GMC Sierra 2500 HD 8.1L O2 Oxygen Sensor