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Sierra 18-3719 Pinion Nut Marine Sterndrive Gearcase Replacement

Manufacturer

Picture for manufacturer Sierra

Part Number

18-3719
14 reviews
Sale Price

$5.64

1 left at this price

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Usually delivered within 2 days

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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 Sierra 18-3719 Pinion Nut is a precision-manufactured marine replacement part designed for use in the lower gearcase of OMC Sterndrive/Cobra and MerCruiser stern drive systems. This 5/8" pinion nut secures the pinion gear on the drive shaft within the lower gear housing, making it a critical component for proper gearcase assembly and operation.

Manufactured by Sierra International to meet or exceed OEM specifications, this pinion nut is a direct replacement for multiple original equipment part numbers across major marine engine brands, offering a reliable and cost-effective alternative to OEM parts.

Key Features:

  • Direct replacement for OMC Sterndrive/Cobra lower gear housing assemblies
  • 5/8" pinion nut for secure drive shaft retention
  • Manufactured to meet or exceed OEM specifications
  • Broad cross-reference compatibility across major marine engine brands

OEM Cross-Reference Part Numbers:

  • OMC / Evinrude / Johnson: 314730
  • MerCruiser / Mercury / Mariner: 11-35921
  • Chrysler: 11-F694188, 11-35921, 11-826375
  • Mercury: 11-47411, 11-826375, 11-35921
  • Mallory: 9-78103
  • GLM: 11190

The Sierra 18-3719 is the trusted choice for marine technicians and boat owners performing lower unit gearcase rebuilds or repairs on OMC Sterndrive/Cobra and MerCruiser applications.

was unable to apply 20% off shipping.

found what I was looking for fast .

Best price anywhere!

You had a part I couldn't find elsewhere

Fast and easy to find my parts and purchase them

PRICE WAS EXCELLENT, PRODUCT WAS EXCELLENT, THREE DAY WAIT TO BE SHIPPED WAS LESS THAN EXCELLENT. YES, I SAW THAT WHEN I ORDERED, $20 FOR TWO DAY SHIPPING WAS A WAIST AS IT TOOK THREE DAYS AND A SUNDAY (4) DAYS PLUS 2 DAYS SHIPPING TIME 6 DAYS. TRACKIN

Best price fast shipping. will deffinitly order again

Great customer service, ships fast. Will buy from again

Ordered a Thule ski rack. Best price on the web. Prompt delivery as promised, however, did not get shipping email and tracking no until after delivery was already made. The customer service that I experienced trying to get info on delivery was less than desirable. Four stars o ly.

Placed order #27494 for some bumpstops. Came out $40 cheaper then i could get with reseller discounts elsewhere. Great item, shipped quick, very satisfied.

Item arrived in two days, item was at the best price available, great service will use again!

Easy peasy lemon squeezie

Smooth transaction, very pleased

Fast

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