Heated Oxygen O2 Sensor Upstream and Downstream for Express Silverado Tahoe Savana Sierra C1500 C2500 C3500

Had these installed in my 1999 Escalade 5.7 liter 4x4 a week ago and my check engine light keeps returning! I don’t think I can return these as it’s not an option on my amazon account. The mechanic installed Denso sensors and the check engine lights gone! So these were a true waste of money since I had to buy 4 Denso sensors (2 up & 2 downstream).Update..Amazon customer service came thru and gave me a full refund... thank you Amazon

So bought these to replace my 20 year old ones on my truck they look great and everything for the price why not. turns out that my open loop Bank 1 and bank 2 sensors 1 wouldn’t close due to this either not being pinned correctly or just bad luck bought OEM and now I have close loop wasn’t able to test rear as I have mine are deleted

These were a waste of my time and my money I had high hopes when I installed them and everything had worked just fine. After a short drive the engine light came on so I drove home and plugged in only to find out that the upstream was not working at all turns our these were broken but the downstreams worked fine. DO NOT waste your money on these buy a better more reliable brand for a few dollars more.

Amazon states this would fit my 2002 Silverado 1500 but it does not. I waited too long to install these and now the return window is closed. The connector is wrong for the back 2 sensors (should be square) and reversed on the front 2 sensors. I was able to modify the front 2 by removing the alignment tab. Don't buy these.

Upstream sensors failed approximately 5 minutes during drive cycle and one of downstream failed next day

Price was very good

Perfect fit