[Sigh] the uncomplicated time with my old 1989 300CE is gone. Two level measures at two specific moments when the AT fluid reaches the specified temperature. Supposed you have AT fluid temp over one range, say 120F, what do you do? wait and re-measure again and again until it cools down to 80F?
And if one level is OK and the other not, should the fluid be added or extracted? either way it will affect the good one.
My expensive approach: I took it to my indy, got it flushed and refilled and hope that it is OK. I can't never be sure
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