I was driving along today in the 300D, it has 225/60/15 tires all around, and the speedometer was showing 70 mph, and the tachometer was showing 3400 rpms on level ground. Anybody have some sort of equation they use so I can determine the actual speed I was going? Because the 300SD has 205/70/14 tires, and 70 is closer to probably 3100 rpms on it.
-Joe

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'81 MB 300SD, '82 MB 300D Turbo (sold/RIP), '04 Lincoln Town Car Ultimate

Sooner or later every car falls apart, ours does it later!
-German Narrator in a MB Promotion Film about the then brand new W123.