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Sierra 18-1155 Marine Ball Bearing for MerCruiser Sterndrive Lower Unit

Manufacturer

Picture for manufacturer Sierra

Part Number

18-1155
13 reviews
Sale Price

$45.91

3 left at this price

delivery box

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 International 18-1155 is a precision-engineered marine ball bearing designed as a direct replacement for MerCruiser sterndrive lower units. Built to meet or exceed original equipment specifications, this reverse gear ball bearing delivers reliable performance and extended service life in demanding marine environments.

Key Features:

  • Precision ball bearing construction for smooth, low-friction operation
  • Meets or exceeds OEM specifications and quality standards
  • Backed by Sierra's Limited Lifetime Warranty
  • Direct drop-in replacement — no modifications required

Compatible Sterndrive Models:

  • MerCruiser IA, IB, IC & EZ Shift
  • MerCruiser MC-I, R, and MR
  • MerCruiser Alpha One & Alpha One Gen II

OEM & Cross-Reference Part Numbers:

  • Mercury Marine / MerCruiser: 30-88957A1, 30-88957T, 30-35914, 30-17927
  • GLM: 21620
  • Mallory: 9-75114

Sierra International is a trusted name in aftermarket marine parts, offering boaters a cost-effective alternative to OEM components without sacrificing fit, function, or durability.

Good prices. Shipping is a bit slow. I would order for autoplicity again.

good seller, fast delivery. They sent me a email telling me that they had sent the product and gave me the tracking number so i would know when it would arrive. The wheel lock product was listed accuately and fit nicely on my truck. <br>

very good

Easy and great prices, Thanks!

Excellent

Quick and Easy, now I wait to see how my item looks when it arrives and report back.

First time that I have tried Autoplicity. Best price on the brand/part that I really wanted. Fast turnaround, and they have great customer service. Will use again. Highly recomend!

Not bad price

Great!

quick response and unbelievably CHEAP prices.

Great place to do business with! Exactly what I ordered for a great price and even showed up 3 days early. You can not ask for anymore than this!!!!!

Now problem with Autoplicity---you contact them---they respond--Thanks

Best Price around. Ordered Friday Shipped Monday. Thanks

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