Drivetrain› Automatic Transmissions and Components
TCI Automotive
Speedometer GM Drive Gear: 20 tooth spline, Blue
SKU: T00M 880002
Easy — 1–2 hours
Description
This plastic gear is aqua blue and sold individually. It is intended for use with GM Turbo-Hydramatic and PowerGlide transmissions. The gear measures 2.25" x .305" x .800" and replaces GM part number 3987920. TCI offers various speedometer gears to accurately display your vehicle's speed when tire size or gear ratios are changed.
Fitment
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Specifications
| Brand | TCI Automotive |
| Part Number | T00M 880002 |
Buy with Confidence
Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.
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