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Sierra 18-2180 Sterndrive Drive Shaft for MerCruiser MR/Alpha One

Manufacturer

Picture for manufacturer Sierra

Part Number

18-2180
10 reviews
Sale Price

$137.03

1 left at this price

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Usually delivered within 2 days

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Fitment guaranteed

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Product Details

The Sierra 18-2180 is an aftermarket replacement sterndrive drive shaft designed for MerCruiser MR and Alpha One Gen I lower unit gearcases. It directly replaces Mercury MerCruiser OEM part number 45-42634, offering a reliable, cost-effective solution for stern drive servicing and lower unit rebuilds.

Key Features:

  • Direct aftermarket replacement for Mercury MerCruiser OEM part 45-42634
  • Compatible with all MR and Alpha One Gen I lower unit configurations
  • Also fits older pre-MR units that have been retro-fitted with MR/Alpha lower units
  • Engineered to meet or exceed original equipment standards in the harsh marine environment
  • Manufactured by Sierra International, a trusted supplier to OEM engine builders and boat manufacturers

Sierra International designs its marine components to withstand the demanding conditions of saltwater and freshwater use alike. The 18-2180 drive shaft is a direct-fit replacement that restores proper power transfer from the engine to the lower unit gearcase, helping maintain drivetrain integrity and performance.

OEM Cross-Reference: Mercury MerCruiser 45-42634

Great prices. Easy to navigate around website. Have what i need in stock

Fast! Fast, fast, Fast! Fast, fastFast! Fast, fast

I'm always had a great experience!

goodprice

The item was perfect just like from the store and shipped berry fast!!<br><br>Lower price than eBay or Amazon. <br><br>Will recommend to friends.

best price on harley filters from wix. next is to see how fast shipping is

It was easy to find the things I needed!

worked perfect

Great customer service. Good price. Quick shipment. Would definately reccomend this company.

Best price found. Excellent customer service. Thank You!

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