I checked the differential in my sister's 300TE the other day(just because), and it was a 3.27 indeed. I don't even know if the gearing ratios are the same. TC lockup must occur at a greater speed than my SE, or perhaps the speedometer is off.

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1987 300SDL (324000)

1986 Porsche 951 (944 Turbo) (166000)

1978 Porsche 924 (99000)

1996 Nissan Pathfinder R50 (201000)