HomeBelts and Cooling > Gaskets and Sealing SystemsFel-Pro 35703 Engine Coolant Thermostat O-Ring
Part #: 35703

Fel-Pro 35703 Engine Coolant Thermostat O-Ring

⚙️ 64 vehicles fit this part
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Select your vehicle to confirm fitment
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OE Direct Replacement — Bolt-on fit, no modifications needed
🚗Fitment: Ram and Dodge, 2500, 3500, Ram 2500, and Ram 3500
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Reliable Engine Coolant Thermostat O-Ring for Dodge Ram 2500 and 3500

The Fel-Pro 35703 Engine Coolant Thermostat O-Ring is designed to provide a secure seal in the cooling system of Dodge Ram 2500 and Ram 3500 models. This premium-grade O-ring ensures proper thermostat function by preventing coolant leaks and maintaining system integrity.

Key Features of Fel-Pro 35703 Engine Coolant Thermostat O-Ring

  • Premium grade material for enhanced durability and heat resistance
  • Specifically engineered for Dodge Ram 2500 and Ram 3500 vehicles
  • Precise fitment to ensure a leak-free seal around the thermostat housing
  • Compatible with engine coolant systems requiring a reliable sealing solution
  • Manufactured by Fel-Pro, a trusted name in gaskets and sealing systems

Detailed Product Description

The Fel-Pro 35703 O-ring is a critical component in the engine coolant thermostat assembly for Dodge Ram 2500 and 3500 trucks. Made from premium-grade materials, this O-ring withstands high temperatures and pressure fluctuations within the cooling system. Its precise dimensions ensure a tight seal, preventing coolant leaks that can lead to engine overheating or inefficient thermostat operation. This part is categorized under Belts and Cooling > Gaskets and Sealing Systems, emphasizing its role in maintaining the integrity of the engine’s cooling circuit.

Common Applications and Issues Addressed

  • Prevents coolant leaks around the thermostat housing
  • Maintains proper thermostat function and engine temperature regulation
  • Reduces risk of engine overheating due to coolant loss
  • Eliminates coolant seepage that can cause corrosion or damage to engine components
  • Ensures reliable sealing in Dodge Ram 2500 and Ram 3500 cooling systems

Installation Notes and Tips

  • Ensure the thermostat housing surface is clean and free of debris before installation
  • Lubricate the O-ring lightly with engine coolant or appropriate lubricant to ease installation
  • Check the O-ring for any damage or deformities prior to fitting
  • Install the O-ring carefully to avoid twisting or pinching, which can compromise the seal
  • Tighten thermostat housing bolts to manufacturer specifications to prevent leaks

Quality Assurance and Warranty

Fel-Pro parts are manufactured to meet or exceed OEM specifications, ensuring reliable performance in demanding automotive environments. The 35703 Engine Coolant Thermostat O-Ring undergoes rigorous quality control to guarantee fitment and durability. While specific warranty details may vary, Fel-Pro products typically come with a limited warranty against defects in material and workmanship.

This part fits 64 vehicles. Search below:

YearMakeModelLitersCylindersPositionNotes
2024Ram25006.7LL6N/A
2024Ram35006.7LL6N/A
2023Ram25006.7LL6N/A
2023Ram35006.7LL6N/A
2022Ram25006.7LL6N/A
2022Ram35006.7LL6N/A
2021Ram25006.4LV8N/A
2021Ram25006.7LL6N/A
2021Ram35006.4LV8N/A
2021Ram35006.7LL6N/A
2020Ram25006.4LV8N/A
2020Ram25006.7LL6N/A
2020Ram35006.4LV8N/A
2020Ram35006.7LL6N/A
2019Ram25006.4LV8N/A
2019Ram25006.7LL6N/A
2019Ram35006.4LV8N/A
2019Ram35006.7LL6N/A
2018Ram25006.4LV8N/A
2018Ram25006.7LL6N/A
2018Ram35006.4LV8N/A
2018Ram35006.7LL6N/A
2017Ram25006.4LV8N/A
2017Ram25006.7LL6N/A
2017Ram35006.4LV8N/A
2017Ram35006.7LL6N/A
2016Ram25006.4LV8N/A
2016Ram25006.7LL6N/A
2016Ram35006.4LV8N/A
2016Ram35006.7LL6N/A
2015Ram25006.4LV8N/A
2015Ram25006.7LL6N/A
2015Ram35006.4LV8N/A
2015Ram35006.7LL6N/A
2014Ram25006.4LV8N/A
2014Ram25006.7LL6N/A
2014Ram35006.4LV8N/A
2014Ram35006.7LL6N/A
2013Ram25006.7LL6N/A
2013Ram35006.7LL6N/A
2012Ram25006.7LL6N/A
2012Ram35006.7LL6N/A
2011Ram25006.7LL6N/A
2011Ram35006.7LL6N/A
2010DodgeRam 25006.7LL6N/A
2010DodgeRam 35006.7LL6N/A
2009DodgeRam 25005.9LL6N/A
2009DodgeRam 25006.7LL6N/A
2009DodgeRam 35006.7LL6N/A
2008DodgeRam 25005.9LL6N/A
2008DodgeRam 25006.7LL6N/A
2008DodgeRam 35006.7LL6N/A
2007DodgeRam 25005.9LL6N/A
2007DodgeRam 25006.7LL6N/A
2007DodgeRam 35005.9LL6N/A
2007DodgeRam 35006.7LL6N/A
2006DodgeRam 25005.9LL6N/A
2006DodgeRam 35005.9LL6N/A
2005DodgeRam 25005.9LL6N/A
2005DodgeRam 35005.9LL6N/A
2004DodgeRam 25005.9LL6N/A
2004DodgeRam 35005.9LL6N/A
2003DodgeRam 25005.9LL6N/A
2003DodgeRam 35005.9LL6N/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:

1140315015708AB5086740AAC31858WO8674

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