The following chart has been updated and replaces the speedometer gear chart shown in Section 7A of the 1990 Grand Am Service Manual, Pontiac Page 7A-34.
Some vehicles are equipped with an internal vehicle speed sensor and the number of rotor teeth is included on the chart.
General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.