- Transmission & Drivetrain
- Automatic Transmission Components
- TCI Speedometer Gears and Accessories
TCI Speedometer Gears are precision machined from high-quality materials and designed to fit most popular transmissions. Speedometer gears include both a drive and a driven gear. The drive gear is located on the transmission's output shaft. The driven gear is positioned in a removable housing that is typically located in the transmission's tailhousing. Chrysler and Ford speedometer gears are built into the outer shaft and can be used on any Chrysler or Ford transmission. Choose from many gear options with a variety of tooth counts. Whether you have a GM, Ford, or Chrysler vehicle, the formula below is useful when no established baseline exists.
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| # Drive Teeth x Axle Ratio x Tire Rev. per Mile 1001 | = # Driven Teeth | |
Use the following formula to calculate the Tire Rev. per Mile for the above formula.
| Tire Rev. per Mile = | 20168 Tire Diameter (inches) | |
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Ensure your speedometer reads accurately and reliably with the TCI Speedometer Gears and Accessories line. Designed for a wide range of automatic transmissions like 700R4, TH350, TH250, and others, these components let you fine-tune the driven and drive gear ratios to match tire size, axle ratio, or transmission swap changes with confidence.
Each speedometer driven gear housing is precision-machined to replace OEM housings when you upgrade to larger tires or modify gearing. The housings drop into the removable portion of your tailshaft, and you get various tooth-count options (34-39 teeth, 40-45 teeth, etc.) to dial in speed accuracy after changes.
If you’re running a GM 700R4, you’ll want the correct speedometer drive gear that matches your drive gear’s tooth count to avoid misreadings. TCI offers drive gear options so you can maintain precise calibration after a transmission swap or ratio change.
These accessories not only improve accuracy, but also protect your transmission components: using the right housing prevents damage common with improperly meshed gears, reduces unwanted wear, and ensures your speedometer, odometer, and electronic systems are all aligned.
Don’t accept speed errors or guesswork—get the correct gear and housing. Whether you need a speedometer driven gear, a speedometer drive gear 700r4, or a 700r4 speedo drive gear, TCI’s selection helps you restore precision quickly. Add these TCI speedometer gears and accessories to your build and ride true, mile after mile.