Jeep 2006 Wrangler Owner's Manual page 285

With the engine at normal operating temperature (but
not running), check the cooling system pressure cap for
proper vacuum sealing by draining a small amount of
antifreeze/coolant from the radiator drain cock. If the cap
is sealing properly, the antifreeze/coolant will begin to
drain from the coolant recovery bottle. DO NOT RE-
MOVE THE COOLANT PRESSURE CAP WHEN THE
COOLING SYSTEM IS HOT.
Cooling System — Drain, Flush, And Refill
At the intervals shown in the appropriate "Maintenance
Schedule," the system should be drained, flushed, and
refilled.
MAINTAINING YOUR VEHICLE 285
If the solution is dirty and contains a considerable
amount of sediment, clean and flush with reliable cooling
system cleaner. Follow with a thorough rinsing to remove
all deposits and chemicals. Properly dispose of old
antifreeze/coolant solution.
Discard old antifreeze/coolant solution according to rec-
ommended procedure.
Selection Of Engine Coolant
Use only the manufacturer's recommended antifreeze/
coolant, refer to Fluids, Lubricants, and Genuine Parts for
correct antifreeze/coolant type.
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