ACDelco Heavy Duty Corrosion Protector (XLI)

ACDelco Heavy Duty Corrosion Protector (XLI)

ACDelco Heavy Duty Corrosion Protector (XLI) - is a water based, low toxicity, environmentally friendly, nitrite free carboxylate inhibitor.


  • Corrosion Protection
  • Wide Service Application 
  • Long service life
  • Improved economics
  • Excellent toxicological and environmental aspects, less fluid disposal 
  • Easy Testing: Inhibitor concentration testing can be easily done using a brix refractometer.


Your engine overheating could be a sign of:

  • Low levels of engine coolant.
  • Problems with coolant flow.
  • Incorrect concentrations of water to coolant.


  • The product exhibits low depletion rates and does not require the addition of supplemental coolant additives with correct maintenance practices.  
  • Dilution of ACDelco XLI by more than 25% will reduce inhibitor performance.
  • ACDelco XLI protects against erosion, corrosion and cavitation of cooling system components.  ACDelco XLI is ready to use without dilution.


Q: Does coolant only cool my engine?
A: No, coolant not only cools the engine, but very
importantly ensure superior protection against corrosion in engines, water
pumps and radiators, including aluminum, iron, copper and solder alloys.

Q: How can I reduce the amount of deposits that forms inside my cooling system that cause my engine to overheat?
A: Heat transfer in the cooling system can be improved by choosing a product that is silicate and phosphate free (ACDelco Heavy Duty Corrosion Protector (XLI)) that does not contribute to deposit build up, as can be seen with phosphate and silicate containing coolants, which can help maintain heat transfer efficiency.

Q: How can I choose a coolant that will protect my vehicle’s cooling system?
A: Select a good coolant approved by your vehicle
manufacturer that protects the cooling system components against erosion,
corrosion and cavitation. This cause wear that will reduce the active service
life of the engine and cooling system components.

Q: Can coolant color be used to determine what product I can use?
A: No. Coolant color can no longer be used to determine the correct product to add to your system