The 2021 Ram 1500 uses Mopar Antifreeze/Coolant Type 2 (OAT), a long-life coolant designed for FCA vehicles. It is typically used in a 50/50 premixed solution or as concentrate that must be diluted with distilled water according to the product label and the owner's manual.
The right coolant type
To safeguard the cooling system and warranty, choose coolant labeled as Mopar Antifreeze/Coolant Type 2 or an aftermarket coolant that explicitly meets Chrysler's Type 2 OAT specification and is approved for use in FCA/Dodge/Jeep vehicles. These formulations are designed to work with the Ram's cooling system components, including the radiator, thermostat, water pump, and heater core.
Note: Do not use coolant intended for other brands if it does not specify compatibility with Chrysler/Jeep/Dodge Type 2 OAT cooling systems. Dex-Cool (GM) or HOAT formulations not approved for FCA vehicles can cause deposits or corrosion.
- Mopar Antifreeze/Coolant Type 2 (OAT) — the OEM-recommended option; available premixed (commonly 50/50) or concentrate to mix with distilled water per label.
- Aftermarket long-life OAT coolant labeled as compatible with Chrysler/Jeep/Dodge and meeting the Type 2 specification (check the product label for Chrysler compatibility).
- Avoid non-OAT or non-compatible formulas, including Dex-Cool or HOAT products, unless explicitly approved for FCA vehicles.
Always use distilled water for concentrate mixes if you purchase concentrate. The typical target is a 50/50 mix unless the label specifies otherwise, which helps protect against freezing and boiling while maintaining corrosion protection.
Maintenance considerations
Regularly check the reservoir level when the engine is cold, and inspect coolant condition for color and cleanliness. If you suspect a leak or overheating, have the system pressure checked by a qualified technician. When replacing coolant, flush the system and replace with the same Type 2 OAT coolant per Mopar guidance or your dealer’s service recommendations.
Engine variations and cautions
Whether your Ram 1500 uses the 3.6L Pentastar, the 5.7L Hemi, or the 3.0L EcoDiesel, the coolant specification remains the Type 2 OAT-compatible coolant. Always confirm at the dealer or in the owner's manual if a specific engine requires a particular formulation or replacement interval.
Summary
The 2021 Ram 1500 requires Mopar Antifreeze/Coolant Type 2 (OAT). Use premixed 50/50 or concentrate mixed with distilled water. Choose Mopar Type 2 or an aftermarket coolant explicitly labeled as compatible with Chrysler/Jeep/Dodge Type 2 OAT specifications, and avoid non-approved formulations. Always follow the owner's manual and dealer guidance for maintenance intervals.