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ACDelco 3987921 Speedometer Drive Gear for GM Vehicles

(GMC G2500 1982-84, C1500 1985, C3500 1986, Safari 1985, 1987-88, S15 1983-85, 1987-88, C1500 Suburban 1985, G3500 1982-84, C2500 Suburban 1986 + 35 more models)

Manufacturer

Picture for manufacturer ACDelco

Part Number

3987921
16 reviews
Sale Price

$11.21

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No Hassle Returns

No Hassle Returns

Live-in-stock inventory

Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The ACDelco 3987921 is a GM Original Equipment speedometer drive gear designed to restore proper speedometer operation in compatible GM vehicles. This critical transmission component mounts directly on the transmission output shaft and meshes with the driven gear to transmit rotational data to the speedometer cable and mechanical speedometer.

Key Features:

  • GM Original Equipment design ensures precise fit and function
  • Manufactured to OEM specifications for durability and longevity
  • Direct replacement for worn or damaged factory speedometer drive gears
  • Maintains accurate speedometer readings when properly installed
  • Engineered specifically for GM transmission applications

This speedometer drive gear is built to deliver the same performance and service life as the original factory component. Proper speedometer function is essential for legal operation and accurate mileage tracking, making timely replacement of worn drive gears an important maintenance consideration.

Products specifications

Fits

GMC G2500 1982-84, C1500 1985, C3500 1986, Safari 1985, 1987-88, S15 1983-85, 1987-88, C1500 Suburban 1985, G3500 1982-84, C2500 Suburban 1986, G1500 1983, R3500 1987, R2500 Suburban 1987; Chevrolet Camaro 1982-84, S10 1982-88 + 30 more models

None

I didn't see an estimated ship/arrival time

Easy to find parts and checkout.

very good

Easy transaction.

They where to big to fit but everything else was good on how fast was delivered n price but just not right thanks

Order confirmation was unclear. It did not provide the carrier or a tracking number that was recognized by USPS, UPS, of FedEx. Used contact form on website to request clarification, but received no reply. Order took a little longer than expected to ship,

Great price and no shipping!!!! Shipped and received quickly

Thank You!

Quick and easy!

Best price I could find on the net and super fast shipping.

Fast Shipping. Hard to find item. Thanks

Great Prices and fast, fast shipping. I will definitely do business with them again.

Good price just hope it's not too good to be true. Here's to hoping.

easy and simple. thanks.

Best price and super fast shipping. Only issue was that their online order status system was really far behind! The system said my order was "pending" and it had been shipped. Later it said "processing" and it was on my doorstep. Not a big deal and certainly better than the opposite (they tell you something has happened when it hasn't) and doesn't keep them from being a 5 star seller in my book.

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