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Sierra 18-2257 Mercruiser Upper Gear Kit 1.65:1 Ratio Inline 6 Cylinder

Manufacturer

Picture for manufacturer Sierra

Part Number

18-2257
11 reviews
Sale Price

$558.87

1 left at this price

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Usually delivered within 2 days

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Product Details

The Sierra 18-2257 is a complete upper gear kit designed as a direct replacement for MerCruiser stern drives equipped with inline 6-cylinder engines running a 1.65:1 gear ratio. This comprehensive kit includes all the bearings, seals, gaskets, and gear components needed to fully rebuild the upper unit, making it an ideal solution for a thorough outdrive service or repair.

This kit replaces OEM MerCruiser part number 43-803112T1 and is also cross-referenced with GLM part number 11225. Sierra parts are engineered to meet or exceed original equipment specifications, ensuring reliable, long-lasting performance.

Gear Specifications:

  • Gear Ratio: 1.65:1
  • Driver Gear: 24 teeth
  • Driven Gear: 24 teeth
  • Application: MerCruiser Alpha One R/MR/Alpha One stern drives with inline 6-cylinder engines (1983–1991)

Kit Includes:

  • 18-2203 Upper Unit Gear Set
  • 18-2648 Upper Unit Seal Kit
  • 18-2619-1 Outdrive Gasket Set
  • 18-2743 Outdrive Mounting Gasket
  • 18-1160 Drive Bearing Kit
  • 18-1161 Tapered Roller Bearing
  • 18-1165 Tapered Roller Bearing

OEM Cross-References:

  • MerCruiser: 43-803112T1
  • GLM: 11225

Sierra's 18-2257 upper gear kit delivers a complete, confidence-inspiring rebuild in a single part number, eliminating the need to source individual components separately.

Second time customer of Autoplicity: Ordered Husky Liners Weatherbeater Floor mats for a 2012 Toyota Tundra, Called in this morning to verify availability, call answered on second ring, great service placed the order immediately. Haven't even received the product yet but the service has been so outstanding had to let everyone know this company is for real. Best pricing online, wont buy products anywhere else.<br><br>Justin Myers

very easy to find my auto part and easy to pay ! thank you!

Please require signature for delivery!

good, but would like something that tells you whats the cut off time for over night shipping

I was told about Autoplicity from a friend on a car forum site that I wouldn't be disappointed with the price, quality and shipping. <br><br>I ordered my part on 7-18-12 and received my item the very next day. That's about as fast as getting some parts from the local auto parts store when they have the parts stocked in an outlying warehouse.<br><br>I will certainly look to Autoplicity first when I need to order engine and other car parts for my 87' Monte Carlo SS<br><br><br><br>

Liked using Amazon

Very pleased with the ordering process. Did lots of research on the product I ordered and autoplicity was able to beat the price of any local carrier of this product by $80. Even better that they offered free shipping because it is a heavy item.

Fast service and great prices. knowledgable sales persons, Hugh in stock items. Packing was excellent, doubled boxed.

Found what I wanted at a good price.

good price and the part was here in just a few days.

Great price, problem with the manufacturer shipping it out, but was rectified by Autoplicity. Very good follow up customer service.

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