2000 Ford Windstar torque converter. Intermittant lock up.Whats the problem?

Stutter in shifting when running, torque converter locking up intermittantly

Try dropping and cleaning the pan, changing the filter, and refilling with Mercon V. If the problem does not go away, the clutch packs may be shot and you're facing a rebuild. These vehicles need this done at least every 30,000 miles. They are very hard on transmissions. Be sure to check for codes, also.

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