Service Information: Overview
CAUTIONLONG TERM USE OF IMPROPER ENGINE COOLANT MAY CAUSE COOLING SYSTEM DETERIORATION THAT COULD RESULT IN LEAKS AND/OR COMPONENT FAILURE.
The 1999 Mercury Cougar is equipped with new orange-colored Ford Extended Life Engine Coolant (F6AZ-19544-AA) that does not need to be changed for 240,000 km (150,000 miles). The balance of the North American Ford and Lincoln/Mercury product line continues to be equipped with conventional green-colored Ford Premium Engine Coolant (E2FZ-19549-AA) which requires changing at shorter intervals.
Vehicles equipped with the new extended life coolant have an underhood Cooling System Instructions label which states:
"Use only orange-colored, silicate-free engine coolant meeting Ford specification WSS-M97B44-D or meeting the DEX-COOL(R) specification. See Owner Guide."
Extended Life Coolant usage can also be verified by the orange color of the coolant in the vehicle's overflow or degas bottle.