coolants should only be mixed with distilled or even better de-ionized water @
a 50/50 mix. These coolants over time will degrade and unlike the coolants of
the past doing a visual check of the coolant typically revealed its condition.
This does not tell the whole story with today’s long life coolants, in fact
these coolants may look perfectly fine even with as many miles 60,000 miles!
Today's long life coolants must be tested by a competent technician to ensure
it has the correct corrosion inhibitors, corrosion can develop as air enters
the system due in part to a weak radiator cap, leaking hose etc... Testing ph.
balance for acidity is one way; this is done with test strips