Sure they do, but 55K is rather early, unless you're driving a 3.0L Misubishi engine, like I had in my LeBaron!

One other thought is that your transmission modulator may have a leaky diaphragm. It's an easy check - disconnect the vacuum line at the modulator and see if it's wet with transmission fluid on the inside.

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95 E320 Cabriolet, 169K