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at 55mph..in 5th gear with 30's it says 3500


Unless your axles have 5.29's in them (incredibly unlikely) your tach or speedo is simply off. Speedo is easiest to check with a GPS, or even a passenger with a stopwatch and an open road, milepost markers and some basic math.

1987 Raider, 346K miles and going strong -31" tires, otherwise stock.
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