Page 288 of 347

3. Step back while the pressure releases.
4. When you are sure that all the pressure has been released, use the
cloth to turn it counterclockwise and remove the cap.
5. Fill the coolant reservoir slowly with the proper coolant mixture, to
within the COLD FILL RANGE or the FULL COLD level on the reservoir.
If you removed the radiator cap in an overflow system, fill the radiator
until the coolant is visible and radiator is almost full.
6. Replace the cap. Turn until tightly installed. Cap must be tightly
installed to prevent coolant loss.
After any coolant has been added, check the coolant concentration (refer
toChecking engine coolant). If the concentration is not 50/50, drain
some coolant and adjust the concentration. It may take several drains
and additions to obtain a 50/50 coolant concentration.
Whenever coolant has been added, the coolant level in the coolant
reservoir should be checked the next few times you drive the vehicle. If
necessary, add enough 50/50 concentration of engine coolant and
distilled water to bring the liquid level to the proper level.
If you have to add more than 1.0 quart (1.0 liter) of engine coolant per
month, have your authorized dealer check the engine cooling system.
Your cooling system may have a leak. Operating an engine with a low
level of coolant can result in engine overheating and possible engine
damage.
Recycled engine coolant
Ford Motor Company does NOT recommend the use of recycled engine
coolant since a Ford-approved recycling process is not yet available.
Used engine coolant should be disposed of in an appropriate
manner. Follow your community’s regulations and standards for recycling
and disposing of automotive fluids.
Coolant refill capacity
To find out how much fluid your vehicle’s cooling system can hold, refer
toMaintenance product specifications and capacitiesin this chapter.
Fill your engine coolant reservoir as outlined previously in theAdding
engine coolantsection.
Maintenance and Specifications
288
2012 MKZ(378)
Owners Guide, 1st Printing
USA(fus)
Page 289 of 347

Severe climates
If you drive in extremely cold climates:
•It may be necessary to increase the coolant concentration
above 50%.
•NEVER increase the coolant concentration above 60%.
•A coolant concentration of 60% will provide improved freeze
point protection. Increased engine coolant concentrations
above 60% will decrease the overheat protection
characteristics of the engine coolant and may cause engine
damage.
•If available, refer to the chart on the coolant container to
ensure the coolant concentration in your vehicle will provide
adequate freeze protection at the temperatures in which you
drive in the winter months.
If you drive in extremely hot climates:
•It is still necessary to maintain the coolant concentration
above 40%.
•NEVER decrease the coolant concentration below 40%.
•Decreased engine coolant concentrations below 40% will
decrease the corrosion/freeze protection characteristics of the
engine coolant and may cause engine damage.
•If available, refer to the chart on the coolant container to
ensure the coolant concentration in your vehicle will provide
adequate protection at the temperatures in which you drive.
Vehicles driven year-round in non-extreme climates should use a 50/50
mixture of engine coolant and distilled water for optimum cooling system
and engine protection.
What you should know about fail-safe cooling
If the engine coolant supply is depleted, this feature allows the vehicle to
be driven temporarily before incremental component damage is incurred.
The “fail-safe” distance depends on ambient temperatures, vehicle load
and terrain.
How fail-safe cooling works
If the engine begins to overheat:
•The engine coolant temperature gauge will move to the H (hot) area.
•The
symbol will illuminate.
Maintenance and Specifications
289
2012 MKZ(378)
Owners Guide, 1st Printing
USA(fus)
Page 324 of 347

Your vehicle is very sophisticated and built with multiple complex
performance systems. Every manufacturer develops these systems using
different specifications and performance features. That’s why it’s
important to rely upon your dealership to properly diagnose and repair
your vehicle.
Ford Motor Company has recommended maintenance intervals for
various parts and component systems based upon engineering testing.
Ford Motor Company relies upon this testing to determine the most
appropriate mileage for replacement of oils and fluids to protect your
vehicle at the lowest overall cost to you and recommends against
maintenance schedules that deviate from the scheduled maintenance
information.
Ford strongly recommends the use of genuine Ford replacement parts.
Parts other than Ford, Motorcraftor Ford-authorized remanufactured
parts that are used for maintenance replacement or for the service of
components affecting emission control must be equivalent to genuine
Ford Motor Company parts in performance and durability. It is the
owner’s responsibility to determine the equivalency of such parts. Please
consult yourWarranty Guidefor complete warranty information.
Chemicals or additives not approved by Ford are not required for factory
recommended maintenance. In fact, Ford Motor Company recommends
against the use of such additive products unless specifically
recommended by Ford for a particular application.
Oils, fluids and flushing
In many cases, fluid discoloration is a normal operating characteristic
and, by itself, does not necessarily indicate a concern or that the fluid
needs to be changed. However, discolored fluids that also show signs of
overheating and/or foreign material contamination should be inspected
immediately by a qualified expert such as the factory-trained technicians
at your dealership. Your vehicle’s oils and fluids should be changed at the
specified intervals or in conjunction with a repair. Flushing is a viable
way to change fluid for many vehicle sub-systems during scheduled
maintenance. It is critical that systems are flushed only with new fluid
that is the same as that required to fill and operate the system, or using
a Ford-approved flushing chemical.
Scheduled Maintenance
324
2012 MKZ(378)
Owners Guide, 1st Printing
USA(fus)