Are upstream and down stream oxygen sensor interchangable?

Id bet the post cat sensors arent as wideband as much as the pre cat sensors are. The post just are there to make sure there is a difference between the pre and post to check to make sure the cats are doing their job. So a higher end (with more resolution) really isnt needed in the post cat positions.

I need to replace Bank 2 Sensor 1 on my 2014 Yukon XL, Are all the upstream ones interchangeable or or they specific to a side? If they mention left or right is that as the driver or standing in front of the vehicle looking at it?
PartsGeek has 2 different upstream ACDelco versions which to buy?.
Should i do both upstream together or just the affected one?

tuck16 said:

I need to replace Bank 2 Sensor 1 on my 2014 Yukon XL, Are all the upstream ones interchangeable or or they specific to a side? If they mention left or right is that as the driver or standing in front of the vehicle looking at it?
PartsGeek has 2 different upstream ACDelco versions which to buy?.
Should i do both upstream together or just the affected one?

Click to expand...

Upstream sensors are the same. GM 12583804 - AC Delco 213-3866

Probably best to replace them in pairs. I've got a lazy one so they're both getting changed out. Amazon Prime.

Those are the part numbers for mine, should be the same for you. Double check here:

https://parts-catalog.acdelco.com/catalog/catalog_search.php

The website shows 5 total, 1 labeled downstream right (Part Number: 12609457), one downstream left (Part Number: 12609457), one as upstream and one as upstream left (both Part Number: 12583804) and another one as upstream (Part Number: 213-3866) - not right or left?
Obviously i don't need the downstream ones, but of the three remaining, which do i need for each side?
Thanks

tuck16 said:

The website shows 5 total, 1 labeled downstream right (Part Number: 12609457), one downstream left (Part Number: 12609457), one as upstream and one as upstream left (both Part Number: 12583804) and another one as upstream (Part Number: 213-3866) - not right or left?
Obviously i don't need the downstream ones, but of the three remaining, which do i need for each side?
Thanks

Click to expand...

Ok, the 9457 is for the cats, either side. This is a downstream sensor.

The 3804 and 213-3866 are interchangeable. These are the upstream sensors and for either side. One is GM OE and the other AC Delco. If memory serves, both part numbers are on the box! These are the ones you need.

I paid $39 each last month delivered and they're now $29.99 with Amazon Prime right now.

7/8" wrench or special O2 socket to change them out. A little flat bladed screwdriver or pick will help with the connector on the driver's side, along the transmission.

When I ordered mine from Rockauto, they showed two different sensors and it said that one was if the truck was built/assembled at the Canadian plant, and the other type of sensor was for all other trucks. They showed a picture of the plugs in the notes, and I matched the picture with what mine looks like. Sure enough, my truck was built at the plant in Mexico (according to my VIN) so it doesn't use the Canadian type sensors.