International Truck and Engine Corp offers information for truck and bus owners on benefits of extended-life coolant.
Extended-life coolants use advanced organic acid technology - which depletes much more slowly than traditional coolant additives - to protect the engine. This eliminates the need to add SCAs, extending coolant service intervals and provide superior heat transfer, cavitation protection, and corrosion protection.
International recommends use of Texaco Extended Life Coolant for its engines. Extended-life coolant should only be used on approved engines, as the organic acids can be incompatible with certain metallic and nonmetallic materials. Some brass compounds and some silicone-based seal materials can be adversely affected by prolonged exposure to extended life coolant, particularly in areas where the material is "scrubbed" by coolant moving at high speeds inside the engine.
Many manufacturers are redesigning engines to be compatible with the long-life coolants to help reduce maintenance costs. International recently made changes to the materials used in its engines - particularly the seals - to remain compatible with new extended-life coolants that are using organic acid technology. Specifically, International inline six-cylinder diesel engines manufactured after Aug 29, 1998, are compatible with extended-life coolants, as well as International V-8 diesel engines built since Feb 2, 1999. As of August 2000, these engines are factory-filled with Texaco Extended Life Coolant.
Because the organic acid technology in extended life coolant protects the engine system without use of conventional abrasive corrosion inhibitors such as silicate and phosphate, truck and bus owners will benefit by:
- Avoiding silicate dropout (sometimes called "green goo"), which clogs coolant passageways.
- Reducing water pump seal failures.
- Improving hard water compatibility, reducing hard scale that can deposit.
- Improving maintenance costs. Due to the longer service intervals, fewer labor hours are required and fewer materials need to be purchased.
Although extended-life coolant is compatible with conventional coolant, mixing extended-life coolant with conventional antifreeze to top off leaks will reduce benefits of the extended-life coolant. If mixture with conventional coolant exceeds 10%, the coolant must be maintained as a conventional system using SCAs, or should be drained and flushed, then refilled with new extended-life coolant.
Because extended-life coolant isn't meant to be mixed with conventional coolant, it is dyed a red/orange color, in contrast to conventional green or blue anti-freeze. When servicing extended-life coolant, check to make sure the color is reddish. If it is brown, the carboxylate level may be off. A test kit, available through International dealers, can be used to test the level. If the level is off, coolant can be restored to its long-life condition by flushing the system and replacing it with extended-life coolant, or treat the system like a conventional coolant with SCAs.
Commercial prediluted mixes, such as Texaco Extended Life Coolant, will provide engine protection for about 150,000 miles, 6,000 hours, or 30 months depending on the severity of truck or bus usage. Then to increase benefits of the extended-life coolant further, an extender should be added to the cooling system. Doing so will provide an additional 150,000 miles, 6,000 hours, or 30 months' protection. After 300,000 miles, 12,000 hours, or five years, the coolant should be drained, flushed, and refilled.