I have a 190 E w/ a 2.6 The shift Modulator is red, driver side of the tranns, and is hard as hell to get to without a medical clamp. I used my fishing hook remover to get the cover off and adjust. There is a little T handle inside. Turning it to the left makes the car shift softer and to the right makes it shift harder. I have been told by a tech that if the pressure is to high it can chirp the tires while shifting. He did say that MB Trans last so long because they by nature shift harder, lessing the wear inside. Don't know if this helps at all.
90 190 E 2.6 162K
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"The one who dies with the most toys wins"