FORD 2011 Explorer v.2 - Manual (Page 385)

battery post can cause inaccurate measurements of the battery condition
and potential incorrect system operation.
Note: Electrical or electronic accessories added to the vehicle by the
dealer or the owner may adversely affect battery performance and
durability and may also affect the performance of other electrical
systems in the vehicle.
When a battery replacement is required, the battery should only be
replaced with a Ford recommended replacement battery that matches
the electrical requirements of the vehicle. After battery replacement, or
in some cases after charging the battery with an external charger, the
BMS requires eight hours of vehicle sleep time (key off with doors
closed) to relearn the new battery state of charge. Prior to relearning
state of charge, the BMS may disable electrical features (to protect the
battery) earlier than normal.
ENGINE COOLANT
Checking engine coolant
The concentration and level of engine coolant should be checked at the
intervals listed in scheduled maintenance information. The coolant
concentration should be maintained at 50/50 coolant and distilled water.
Coolant concentration testing is possible with a hydrometer or antifreeze
tester. The level of coolant should be maintained within the COLD FILL
RANGE in the coolant reservoir. If the level falls below, add coolant per
the instructions in the Adding engine coolant section.
Your vehicle was factory-filled with a 50/50 engine coolant and water
concentration. If the concentration of coolant falls below 40% or above
60%, the engine parts could become damaged or not work properly. A
50/50 mixture of coolant and water provides the following:
• Improved freeze protection
• Improved boiling protection
• Protection against rust and other forms of corrosion.
• Enables calibrated gauges to work properly.
When the engine is cold, check the level of the engine coolant in the
reservoir.
Maintenance and Specifications
385
2011 Explorer (exp)
Owners Guide, 3rd Printing
USA (fus)