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Date registered: Aug 2002
Vehicle: 2007 ML320CDI, 1959 220SE, 1971 280SL, 1982 380SL
Location: Clovis, CA
Mentioned: 7 Post(s)
Quoted: 93 Post(s)
Maybe a speedo shop might have the set frequency? If you have a frequency generator, you can figure this out by placing two reference marks on the odometer wheel, one on the far right 1/10th mile wheel and one across from it on the speedo face using tape to mark it with. Keep adjusting your frequency until you can time 60 seconds for the far right wheel to make one exact turn. This will be 60mph. Set your needle at 60mph at this frequency.
This will calibrate the speedometer to match its designed frequency. It will not make up for tire, rear axle, or other potential changes or if you have a speedo designed for a different combination or car.
Last edited by rick; 02-04-2019 at 11:09 AM.