Personally, I'd flush the system and make sure it had the correct stuff in
it. Do you know for sure the orange stuff you have is Dexcool? Is it
actually orange? Is the "current car" a Ford? The only Ford that came with
the orange stuff was the last version of the Mercury Cougar. If it is any
other Ford, then it did not come with the orange stuff from the factory and
you would be smart to flush it out and put in the correct stuff. If the car
is a GM product, then I'd leave in the Dexcool.
I meant to include these references:
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