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I have a 2000 Jaguar S Sedan with 75000 miles. The transmission began slipping and I took it to a very reputable transmission shop and they rebuilt the tranny. It continued to slip so they bought another core with 40000 miles on it and rebuilt that one. It still slips! This garage has built over 70 Jag transmissions and this is the first time they are having a problem. Could it be some kind of electronic problem, switch or cable or something? We don't know what to do next? I called the Jaguar dealership and they were useless.