Ratio Test Form
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Ratio Test Form

To determine the actual ratio of your vehicle, please follow the test outlined below.
  1. Check if the tire pressure is the same as advised by the factory specifications.

  2. Measure (by making chalk or tape marks) a distance of 52 feet 9 1/2 inches.

  3. Unscrew the speedometer cable at the speedometer head.

  4. Mark the inner core with a paper flag, paper clip or preferably a hairpin.

  5. Push or drive the vehicle over the entire distance, counting the full and partial revolutions of the cable.

  6. Always roll the vehicle towards the first (A) marking until you see the inner core start turning to eliminate the gear clearance. Before you start counting, mark the part of the vehicle that is exactly over the beginning of the line. Stop counting when the marked portion of the vehicle is exactly over the end of the line (B).

  7. It is important to verify you have no gear slippage, therefore do the test three times.

  8. Send the "Test Form" along with your gauge for proper calibration.

Test 1 = ________________ Full ________________ Partial
Test 2 = ________________ Full ________________ Partial
Test 3 = ________________ Full ________________ Partial

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