[AOCORRY] 4Pcs Upstream/Downstream O2 Oxygen Sensor for 2003-2014 Chevrolet Tahoe V8 5.3L, 2003-2013 Chevrolet Silverado 1500 V8 6.0L, 2003-2013 GMC Sierra 1500 V8 5.3L

I bough these to replace my 2005 Chevy Avalanche O2 sensors. They bolted up with no problems and have resolved my check engine lights.This is a 4 pack of the same sensors. Your engine codes will tell you which sensor needs replacing. I needed a bank 1 sensor 1 and bank 1 Sensor 2. Some stores will sell you "front" or "back" specific sensors. As far as I can tell, they are the same all around.Bank 1 - Driver's sideBank 2 - Passenger's sideSensor 1 - FrontSensor 2 - BackThey are all easy to see and pretty easy to access and get out. The internet freaked me out with the difficulty factor of removing old sensors since they may become "welded" to the exhaust system.I did buy an O2 Sensor Removal Tool (which helped with torque) - https://www.amazon.com/gp/product/B01C4OB3XC/ref=ppx_yo_dt_b_asin_title_o07_s00?ie=UTF8&psc=1 ,A Sensor Plug Thread Chase Tool (which I didn't use) - https://www.amazon.com/gp/product/B000XETMW0/ref=ppx_yo_dt_b_asin_title_o04_s00?ie=UTF8&psc=1,and some Rust Release Penetrating WD40 (which I didn't use) - https://www.amazon.com/gp/product/B00631GQGW/ref=ppx_yo_dt_b_asin_title_o05_s00?ie=UTF8&psc=1

Installed the parts and my check engine light is still on. Did a diagnostic check and there still showing up as bad sensors. Dont know if all 4 were faulty or what the deal is.

The description indicates sensors for up and downstream. All for sensors arrived with female connectors and the connection requires male leads on the sensor for Chevy Silerado. Should include male to female conversion. Had to rewire the sensor into harness. Not fun in freezing temps, no time to return and replace. Local items 400 times more expensive. Upon researching the replacement types online, will cut them slack as the mfr apparently refuses to simply this device and has many connector types. Great value for the price, and tech savy installer.

I ordered 4 o2 sensors and three of the four have the incorrect connectors which makes them useless! Wasted money on this purchase! Not happy at all!!!

I wouldn't be able to tell you because I put them in my glove compartment and left for vacation. Whenever I came back from vacation they were missing and I had loaned my vehicle to a friend while I was gone. Because she was pregnant.

They fit perfectly, now my Tahoe is running pretty smooth. The price is a bargain compared with auto parts retail stores

Worked out great for an amazing price !!

Not as advertised. Ordered 4 sensors, got 4 but were all upper sensors. They will not fit lower plug in.