This new speedometer driven gear fits 4 speed toploader transmissions. Typically fitted to Toploaders when factory fitted with 3.00 ratio rear end Will work with 3.00 With Black Gear, 3.50 With Pink Gear See attached chart to help you decide what you require based on gearing and tyre height OEM number: C2DZ-17271-G Factory gearing is based on approx 25.4" tall tyre Tech Tip: If you can determine whether your speedometer is reading too slow or too fast, it is worth noting that a lower # of teeth will cause it to turn faster versus a higher # of teeth to turn slower Toploader transmissions were fitted with either of two mainshaft drive gears. Black gears were used for rear end gearing from 2.75 to 3.5 Pink gears were fitted for rear end gearing for 3.5 to 4.11 Use this handy chart to calculate your requirements Based on 25.4" Tall Tyre Driven Gear Pink Gear Black Gear 16 Teeth 3.25 2.75 17 Teeth 3.50 3.00 18 Teeth 3.70 3.25 19 Teeth 3.90 3.36 20 Teeth 4.11 3.55