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Fel-Pro 35921 Engine Coolant Thermostat SealOE Quality 60-Day Returns
Part #: 35921

Fel-Pro 35921 Engine Coolant Thermostat Seal

⚙️ 144 vehicles fit this part
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✅OE Direct Replacement — Bolt-on fit, no modifications needed
🚗Fitment: Hyundai and Kia, Tucson, Veloster N, Sportage, Stinger, Santa Fe, Optima, Sorento, Sonata, Santa Fe Sport, Genesis Coupe, Forte, Forte Koup, Forte5, Rondo, and Magentis
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Overview of Fel-Pro Engine Coolant Thermostat Seal 35921

The Fel-Pro 35921 engine coolant thermostat seal is designed to provide a reliable seal for the thermostat housing in select Hyundai and Kia vehicles. Engineered with precision, this premium-grade seal ensures proper coolant flow and prevents leaks in the cooling system.

  • Premium grade construction for durability and performance
  • Thickness of 5.3 mm for optimal sealing pressure
  • Inside diameter dimensions: 53.7 x 56.9 mm
  • Outside diameter dimensions: 59.5 x 62.7 mm
  • Compatible with multiple Hyundai and Kia models including Forte, Sonata, and Santa Fe

Detailed Product Description and Specifications

The Fel-Pro 35921 thermostat seal is manufactured to meet strict OEM specifications, ensuring a precise fit and effective sealing in the engine coolant system. With a thickness of 5.3 mm, this seal maintains the necessary compression to prevent coolant leaks around the thermostat housing. The inside diameter ranges from 53.7 to 56.9 mm, while the outside diameter measures between 59.5 and 62.7 mm, accommodating the specific thermostat housings found in various Hyundai and Kia models. This seal is constructed from premium materials to withstand the thermal and chemical stresses typical in engine cooling systems.

Compatible Hyundai and Kia Models

This engine coolant thermostat seal is compatible with a range of Hyundai and Kia vehicles, including but not limited to:

  • Hyundai Forte, Forte5, Forte Koup
  • Hyundai Genesis Coupe
  • Hyundai Santa Fe, Santa Fe Sport
  • Hyundai Sonata, Tucson, Veloster N
  • Kia Magentis, Optima, Rondo, Sorento, Sportage, Stinger

Common Applications and Issues Addressed

  • Prevents coolant leaks at the thermostat housing
  • Maintains proper coolant flow for engine temperature regulation
  • Eliminates overheating caused by faulty or worn seals
  • Reduces risk of engine damage due to coolant loss
  • Ensures reliable operation of the thermostat assembly

Installation Notes and Tips

  • Ensure the thermostat housing surface is clean and free of old gasket material before installation
  • Verify the correct orientation of the seal during placement
  • Use appropriate torque specifications when securing the thermostat housing
  • Inspect the thermostat and housing for damage or warping before installing the seal

Quality Assurance and Warranty

Fel-Pro 35921 thermostat seals are manufactured under stringent quality control standards to meet or exceed OEM requirements. The premium grade materials provide resistance to heat, pressure, and coolant chemicals, contributing to long service life. Warranty coverage details should be confirmed with the product documentation or manufacturer.

This part fits 144 vehicles. Search below:

YearMakeModelLitersCylindersPositionNotes
2021HyundaiTucson2.4LL4N/A
2021HyundaiVeloster N2.0LL4N/A
2021KiaSportage2.4LL4N/A
2021KiaSportage2.0LL4N/A
2021KiaStinger2.0LL4N/A
2020HyundaiSanta Fe2.4LL4N/A
2020HyundaiSanta Fe2.0LL4N/A
2020HyundaiTucson2.4LL4N/A
2020HyundaiVeloster N2.0LL4N/A
2020KiaOptima2.4LL4N/A
2020KiaOptima2.0LL4N/A
2020KiaSorento2.4LL4N/A
2020KiaSportage2.4LL4N/A
2020KiaSportage2.0LL4N/A
2020KiaStinger2.0LL4N/A
2019HyundaiSanta Fe2.4LL4N/A
2019HyundaiSanta Fe2.0LL4N/A
2019HyundaiSonata2.4LL4N/A
2019HyundaiSonata2.0LL4N/A
2019HyundaiTucson2.4LL4N/A
2019HyundaiVeloster N2.0LL4N/A
2019KiaOptima2.4LL4N/A
2019KiaOptima2.0LL4N/A
2019KiaSorento2.4LL4N/A
2019KiaSportage2.4LL4N/A
2019KiaSportage2.0LL4N/A
2019KiaStinger2.0LL4N/A
2018HyundaiSanta Fe Sport2.4LL4N/A
2018HyundaiSanta Fe Sport2.0LL4N/A
2018HyundaiSonata2.4LL4N/A
2018HyundaiSonata2.0LL4N/A
2018HyundaiTucson2.4LL4N/A
2018KiaOptima2.4LL4N/A
2018KiaOptima2.0LL4N/A
2018KiaSorento2.4LL4N/A
2018KiaSorento2.0LL4N/A
2018KiaSportage2.4LL4N/A
2018KiaSportage2.0LL4N/A
2018KiaStinger2.0LL4N/A
2017HyundaiSanta Fe Sport2.4LL4N/A
2017HyundaiSanta Fe Sport2.0LL4N/A
2017HyundaiSonata2.4LL4N/A
2017HyundaiSonata2.0LL4N/A
2017KiaOptima2.4LL4N/A
2017KiaOptima2.0LL4N/A
2017KiaSorento2.4LL4N/A
2017KiaSorento2.0LL4N/A
2017KiaSportage2.4LL4N/A
2017KiaSportage2.0LL4N/A
2016HyundaiSanta Fe Sport2.4LL4N/A
2016HyundaiSanta Fe Sport2.0LL4N/A
2016HyundaiSonata2.4LL4N/A
2016HyundaiSonata2.0LL4N/A
2016KiaOptima2.4LL4N/A
2016KiaOptima2.0LL4N/A
2016KiaSorento2.4LL4N/A
2016KiaSorento2.0LL4N/A
2016KiaSportage2.4LL4N/A
2016KiaSportage2.0LL4N/A
2015HyundaiSanta Fe Sport2.4LL4N/A
2015HyundaiSanta Fe Sport2.0LL4N/A
2015HyundaiSonata2.4LL4N/A
2015HyundaiSonata2.0LL4N/A
2015HyundaiTucson2.4LL4N/A
2015KiaOptima2.4LL4N/A
2015KiaOptima2.0LL4N/A
2015KiaSorento2.4LL4N/A
2015KiaSportage2.4LL4N/A
2015KiaSportage2.0LL4N/A
2014HyundaiGenesis Coupe2.0LL4N/A
2014HyundaiSanta Fe Sport2.4LL4N/A
2014HyundaiSanta Fe Sport2.0LL4N/A
2014HyundaiSonata2.4LL4N/A
2014HyundaiSonata2.0LL4N/A
2014HyundaiTucson2.4LL4N/A
2014KiaOptima2.4LL4N/A
2014KiaOptima2.0LL4N/A
2014KiaSorento2.4LL4N/A
2014KiaSportage2.4LL4N/A
2014KiaSportage2.0LL4N/A
2013HyundaiGenesis Coupe2.0LL4N/A
2013HyundaiSanta Fe Sport2.4LL4N/A
2013HyundaiSanta Fe Sport2.0LL4N/A
2013HyundaiSonata2.4LL4N/A
2013HyundaiSonata2.0LL4N/A
2013HyundaiTucson2.4LL4N/A
2013HyundaiTucson2.0LL4N/A
2013KiaForte2.4LL4N/A
2013KiaForte2.0LL4N/A
2013KiaForte Koup2.4LL4N/A
2013KiaForte Koup2.0LL4N/A
2013KiaForte52.4LL4N/A
2013KiaForte52.0LL4N/A
2013KiaOptima2.4LL4N/A
2013KiaOptima2.0LL4N/A
2013KiaSorento2.4LL4N/A
2013KiaSportage2.4LL4N/A
2013KiaSportage2.0LL4N/A
2012HyundaiSanta Fe2.4LL4N/A
2012HyundaiSonata2.4LL4N/A
2012HyundaiSonata2.0LL4N/A
2012HyundaiTucson2.4LL4N/A
2012HyundaiTucson2.0LL4N/A
2012KiaForte2.4LL4N/A
2012KiaForte2.0LL4N/A
2012KiaForte Koup2.4LL4N/A
2012KiaForte Koup2.0LL4N/A
2012KiaForte52.4LL4N/A
2012KiaForte52.0LL4N/A
2012KiaOptima2.4LL4N/A
2012KiaOptima2.0LL4N/A
2012KiaRondo2.4LL4N/A
2012KiaSorento2.4LL4N/A
2012KiaSportage2.4LL4N/A
2012KiaSportage2.0LL4N/A
2011HyundaiSanta Fe2.4LL4N/A
2011HyundaiSonata2.4LL4N/A
2011HyundaiSonata2.0LL4N/A
2011HyundaiTucson2.4LL4N/A
2011HyundaiTucson2.0LL4N/A
2011KiaForte2.4LL4N/A
2011KiaForte2.0LL4N/A
2011KiaForte Koup2.4LL4N/A
2011KiaForte Koup2.0LL4N/A
2011KiaOptima2.4LL4N/A
2011KiaOptima2.0LL4N/A
2011KiaRondo2.4LL4N/A
2011KiaSorento2.4LL4N/A
2011KiaSportage2.4LL4N/A
2011KiaSportage2.0LL4N/A
2010HyundaiSanta Fe2.4LL4N/A
2010HyundaiSonata2.4LL4N/A
2010HyundaiTucson2.4LL4N/A
2010KiaForte2.4LL4N/A
2010KiaForte2.0LL4N/A
2010KiaForte Koup2.4LL4N/A
2010KiaForte Koup2.0LL4N/A
2010KiaMagentis2.4LL4N/A
2010KiaOptima2.4LL4N/A
2010KiaRondo2.4LL4N/A
2009HyundaiSonata2.4LL4N/A
2009KiaMagentis2.4LL4N/A
2009KiaOptima2.4LL4N/A
2009KiaRondo2.4LL4N/A

* 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:

256412G000256412G500C32408C32409

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