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Standard SG2103T Oxygen Sensor - RearOE Quality 60-Day Returns
Part #: SG2103T

Standard SG2103T Oxygen Sensor - Rear

Rear
135 vehicles fit this part
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Fitment: Buick, Cadillac, Chevrolet, and GMC, Acadia, Blazer, Cascada, Corvette, Envision, Equinox, Escalade, Escalade ESV, Express 2500, Express 3500, Impala, Malibu, Regal, Regal Sportback, Regal TourX, Savana 2500, Savana 3500, Sierra 1500, Sierra 1500 Limited, Sierra 2500 HD, Sierra 3500 HD, Silverado 1500, Silverado 1500 LD, Silverado 2500 HD, Silverado 3500 HD, Suburban 3500 HD, Tahoe, Terrain, Traverse, Yukon, and Yukon XL
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Heated Rear Oxygen Sensor for GM Applications

The Standard SG2103T is a heated rear oxygen sensor built for direct replacement in a wide range of Chevrolet, GMC, Buick, and Cadillac applications. It is used to monitor exhaust oxygen content after the catalytic converter, supporting accurate fuel control and emissions system feedback.

  • Heated oxygen sensor for rear position applications
  • Direct-fit replacement for select GM vehicles
  • Supports emissions monitoring after the catalytic converter
  • Cross-references GM OE part number 12643903
  • Standard SG2103T fitment spans 2013-2021 model years

Vehicle Fitment

  • Fits 2019-2021 Chevrolet Blazer, Rear
  • Fits 2017-2021 GMC Acadia, Rear
  • Fits 2016-2020 Buick Envision, Rear
  • Fits 2018-2020 Buick Regal Sportback, Rear
  • Fits 2018-2020 Buick Regal TourX, Rear
  • Fits 2015-2020 Cadillac Escalade, Rear
  • Fits 2015-2020 Cadillac Escalade ESV, Rear
  • Fits 2018-2020 Chevrolet Equinox, Rear
  • Fits 2016-2020 Chevrolet Express 2500, Rear
  • Fits 2016-2020 Chevrolet Express 3500, Rear
  • Fits 2015-2020 Chevrolet Tahoe, Rear
  • Fits 2016-2020 GMC Savana 2500, Rear
  • Fits 2016-2020 GMC Savana 3500, Rear
  • Fits 2018-2020 GMC Terrain, Rear
  • Fits 2015-2020 GMC Yukon, Rear
  • Fits 2015-2020 GMC Yukon XL, Rear
  • Fits 2016-2019 Buick Cascada, Rear
  • Fits 2014-2019 Chevrolet Impala, Rear
  • Fits 2013-2019 Chevrolet Malibu, Rear
  • Fits 2014-2019 Chevrolet Silverado 1500, Rear
  • Fits 2019 Chevrolet Silverado 1500 LD, Rear
  • Fits 2016-2019 Chevrolet Silverado 2500 HD, Rear
  • Fits 2016-2019 Chevrolet Silverado 3500 HD, Rear
  • Fits 2016-2019 Chevrolet Suburban 3500 HD, Rear
  • Fits 2018-2019 Chevrolet Traverse, Rear
  • Fits 2014-2019 GMC Sierra 1500, Rear
  • Fits 2019 GMC Sierra 1500 Limited, Rear
  • Fits 2016-2019 GMC Sierra 2500 HD, Rear
  • Fits 2016-2019 GMC Sierra 3500 HD, Rear
  • Fits 2014-2017 Buick Regal, Rear
  • Fits 2014-2016 Chevrolet Corvette, Rear

What This Sensor Helps Address

  • Check engine light related to rear oxygen sensor performance
  • Incorrect exhaust oxygen readings after the catalytic converter
  • Fuel trim or emissions monitor faults tied to sensor output
  • Slow sensor response from a worn heated oxygen sensor
  • Diagnostic trouble codes associated with rear O2 sensor circuits

Installation Notes

Verify the connector style, sensor location, and engine application before installation. This rear oxygen sensor is intended for the listed Chevrolet, GMC, Buick, and Cadillac fitments, including Silverado 1500, Sierra 1500, Malibu, and Equinox applications. Follow factory service procedures for removal, routing, and torque specifications.

Quality Assurance

Standard replacement sensor engineered for OE-style fit and function in the listed applications. This part cross-references GM OE part number 12643903 for the same application.

BrandStandard
Part NumberSG2103T
HeatedYes

This part fits 135 vehicles. Search below:

YearMakeModelSubmodelLitersCylindersPositionNotes
2021ChevroletBlazer2.5LL4Rear
2021GMCAcadia2.5LL4Rear
2020BuickEnvisionRear
2020BuickRegal Sportback2.0LL4Rear
2020BuickRegal TourXRear
2020CadillacEscalade6.2LV8Rear
2020CadillacEscalade ESV6.2LV8Rear
2020ChevroletBlazer2.5LL4Rear
2020ChevroletEquinox2.0LL4Rear
2020ChevroletExpress 25006.0LV8Rear
2020ChevroletExpress 35006.0LV8Rear
2020ChevroletTahoeRear
2020GMCAcadia2.5LL4Rear
2020GMCSavana 2500Rear
2020GMCSavana 3500Rear
2020GMCTerrain2.0LL4Rear
2020GMCYukonRear
2020GMCYukon XLRear
2019BuickCascadaRear
2019BuickEnvisionRear
2019BuickRegal Sportback2.0LL4Rear
2019BuickRegal TourXRear
2019CadillacEscalade6.2LV8Rear
2019CadillacEscalade ESV6.2LV8Rear
2019ChevroletBlazer2.5LL4Rear
2019ChevroletEquinox2.0LL4Rear
2019ChevroletExpress 25006.0LV8Rear
2019ChevroletExpress 35006.0LV8Rear
2019ChevroletImpala2.5LL4Rear
2019ChevroletMalibu2.0LL4Rear
2019ChevroletSilverado 1500Rear
2019ChevroletSilverado 1500 LDRear
2019ChevroletSilverado 2500 HDRear
2019ChevroletSilverado 3500 HDRear
2019ChevroletSuburban 3500 HDRear
2019ChevroletTahoeRear
2019ChevroletTraverse2.0LL4Rear
2019GMCAcadia2.5LL4Rear
2019GMCSavana 2500Rear
2019GMCSavana 3500Rear
2019GMCSierra 1500Rear
2019GMCSierra 1500 LimitedRear
2019GMCSierra 2500 HDRear
2019GMCSierra 3500 HDRear
2019GMCTerrain2.0LL4Rear
2019GMCYukonRear
2019GMCYukon XLRear
2018BuickCascadaRear
2018BuickEnvisionRear
2018BuickRegal Sportback2.0LL4Rear
2018BuickRegal TourXRear
2018CadillacEscalade6.2LV8Rear
2018CadillacEscalade ESV6.2LV8Rear
2018ChevroletEquinox2.0LL4Rear
2018ChevroletExpress 25006.0LV8Rear
2018ChevroletExpress 35006.0LV8Rear
2018ChevroletImpala2.5LL4Rear
2018ChevroletMalibu2.0LL4Rear
2018ChevroletSilverado 1500Rear
2018ChevroletSilverado 2500 HDRear
2018ChevroletSilverado 3500 HDRear
2018ChevroletSuburban 3500 HDRear
2018ChevroletTahoeRear
2018ChevroletTraverse2.0LL4Rear
2018GMCAcadia2.5LL4Rear
2018GMCSavana 2500Rear
2018GMCSavana 3500Rear
2018GMCSierra 1500Rear
2018GMCSierra 2500 HDRear
2018GMCSierra 3500 HDRear
2018GMCTerrain2.0LL4Rear
2018GMCYukonRear
2018GMCYukon XLRear
2017BuickCascadaRear
2017BuickEnvisionRear
2017BuickRegal2.0LL4Rear
2017CadillacEscalade6.2LV8Rear
2017CadillacEscalade ESV6.2LV8Rear
2017ChevroletExpress 25006.0LV8Rear
2017ChevroletExpress 35006.0LV8Rear
2017ChevroletImpala2.5LL4Rear
2017ChevroletMalibu2.0LL4Rear
2017ChevroletSilverado 1500Rear
2017ChevroletSilverado 2500 HDRear
2017ChevroletSilverado 3500 HDRear
2017ChevroletSuburban 3500 HDRear
2017ChevroletTahoeRear
2017GMCAcadia2.5LL4Rear
2017GMCSavana 2500Rear
2017GMCSavana 3500Rear
2017GMCSierra 1500Rear
2017GMCSierra 2500 HDRear
2017GMCSierra 3500 HDRear
2017GMCYukonRear
2017GMCYukon XLRear
2016BuickCascadaRear
2016BuickEnvisionRear
2016BuickRegal2.0LL4Rear
2016CadillacEscalade6.2LV8Rear
2016CadillacEscalade ESV6.2LV8Rear
2016ChevroletCorvetteStingray6.2LV8Rear
2016ChevroletExpress 25006.0LV8Rear
2016ChevroletExpress 35006.0LV8Rear
2016ChevroletImpala2.5LL4Rear
2016ChevroletMalibu2.0LL4Rear
2016ChevroletSilverado 1500Rear
2016ChevroletSilverado 2500 HDRear
2016ChevroletSilverado 3500 HDRear
2016ChevroletSuburban 3500 HDRear
2016ChevroletTahoeRear
2016GMCSavana 2500Rear
2016GMCSavana 3500Rear
2016GMCSierra 1500Rear
2016GMCSierra 2500 HDRear
2016GMCSierra 3500 HDRear
2016GMCYukonRear
2016GMCYukon XLRear
2015BuickRegal2.0LL4Rear
2015CadillacEscalade6.2LV8Rear
2015CadillacEscalade ESV6.2LV8Rear
2015ChevroletCorvetteStingray6.2LV8Rear
2015ChevroletImpala2.5LL4Rear
2015ChevroletMalibu2.0LL4Rear
2015ChevroletSilverado 1500Rear
2015ChevroletTahoeRear
2015GMCSierra 1500Rear
2015GMCYukonRear
2015GMCYukon XLRear
2014BuickRegal2.0LL4Rear
2014ChevroletCorvetteStingray6.2LV8Rear
2014ChevroletImpala2.5LL4Rear
2014ChevroletMalibu2.0LL4Rear
2014ChevroletSilverado 1500Rear
2014GMCSierra 1500Rear
2013ChevroletMalibu2.0LL4Rear

* Always verify fitment with your vehicle's VIN if unsure. Submodel & trim restrictions may apply.

This part directly replaces or is cross-referenced with the following part numbers:

12643903

Cross-reference numbers are provided for identification purposes only. Always confirm fitment before ordering.

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