these guys are good: http://www.nhspeedometer.com/

Isn't it cable driven in which that or the drive could be at fault? Isolate the problem with the speedometer before sending it out for repair.

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'88 300TE, 175k, black RENNTech 3.6L Recaro C's AMG 1 SOLD
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'94 E320 Cabriolet, 130k, E500 wheels, Emerald green SOLD
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'88 300TE, 229k, dark grey, SOLD
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