OTR Heavy Duty Extended Life Antifreeze/Coolant 50/50 Pre-Mix ensures Expertise Built In™, providing extended service maintenance protection for vehicle’s engine cooling systems that require a heavy duty Nitrite Organic Acid Technology (NOAT) coolant. It is important to change your antifreeze/coolant every 300,000 miles for the purpose of avoiding engine performance issues that ultimately could lead to component failure. This heavy duty antifreeze/coolant fluid offers advanced wet sleeve liner cavitation defense and contains a molybdate and nitrite additive mixture. FleetPride is your First Click in Heavy Duty®.