A Perspective On Extended Service Intervals And Long Life Coolants For Heavy Duty Engines

An overview of extended service interval (ESI) and long life coolant (LLC) and how these topics are related to engine type and duty cycle, to coolant chemistry, and to coolant maintenance practices is presented. For purposes of this paper, ESI is defined as a minimum of 100K miles between routine additions of supplemental coolant additive (SCA). A brief description of Fleetguard ESI/LLC products is given. Finally, a brief status report of work being done to develop industry standards for ESI/LLC products is presented.