During a Dallas press conference, Equilon officials presented statements from engine makers Caterpillar, Detroit Diesel, GM, Mack and Navistar International reiterating their approval of factory fills of this coolant and similar formulations using organic acid technology to achieve extended life up to 600,000 miles.
About two months ago, RoadStar was the first to report of potential coolant seal degradation resulting from the extended life coolant in Cummins N14 engines, resulting in coolant leakage around rocker cover gaskets. Initially, Cummins advised engine owners to replace the ELC coolant with conventional heavy-duty coolant. Later, Cummins and Equilon issued a joint statement recommending the extended life coolant not be drained, and that they were working on a short-term fix and a permanent solution.
Equilon officials noted that even if the engine is experiencing this problem, it's a slow leak, not a critical situation requiring an immediate change to another coolant. "It's not like trucks are running down the road spewing coolant," said Ron Moser, manager of coolants for Equilon.
Today, Equilon told RoadStar that they expect a short-term remedy by the end of the month. This could involve the use of silicate additives, which seem to provide some sort of protection to the silicone seals affected.
In fact, this protective effect means that only the Cummins N14 engines factory filled with the ELC have had this problem. Engines factory filled with traditional coolant and later changed to ELC have not exhibited this problem, according to Equilon officials. They believe the silicates in the initial conventional factory fill provided a protective seal.
John Flaherty, senior research chemist with General Motors, blasted Cummins for the way it has handled this situation. According to Flaherty, Cummins claimed that GM has been having similar coolant problems with its 6.5-liter engines. "I've never seen another company attack another engine manufacturer on such unsubstantiated data," he said. "From the data we have and from the comments we've gotten from Cummins, I think they misunderstand the information that they have. We have much more data than what they were looking at. One problem that we were notified of that they thought was a coolant related problem wasn't coolant-related after all." Flaherty said that GM has used the same coolant technology in passenger cars since 1996 and has yet to have a seal problem. He also advised truck owners to be discriminating in their coolant choice. "Don't buy a coolant just because it's orange," he said. "Not all OAT coolants are the same."
Art Trahan from Ryder also spoke about extensive experience with extended life coolants. Ryder has been testing Texaco ELC since 1993. It has only seen problems in Cummins N14 engines, and notes that it has only seen the leakage in about 3% of the engines.
Officials from Cummins refused to comment while hosting a press conference on an unrelated matter, and instead referred all questions to their Columbus, IN, headquarters.