Genuine Caterpillar Engine Fluids @ PSC Parts Store.com - Order Online - Credit Card or PayPal Accepted - PSC Parts is an authorized CAT Dealer. Cat® ELC incorporates an advanced technology with organic acid corrosion inhibitors for maximum copper, solder, brass, steel, cast iron, and aluminum. protection. Lowers maintenance costs by eliminating the need for supplemental coolant additives, extends coolant change-out intervals, and reduces disposal requirements. Cat ELC is recommended in most Cat machine engine and machines.