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Home  >  Clearance & Non-Stock Parts  >  Non-Stock Parts  > Mercury Racing 450R XL Gearcase 1.60 Ratio 8M0176859

Mercury Racing 450R XL Gearcase 1.60 Ratio 8M0176859

5.44 inch XL standard rotation gearcase for Mercury Racing 450R
Item #: 8M0176859  Cross Reference#: 8M0159651, 8M0176859  
Manufacturer Item: 8M0176859
Manufacturer: Mercury Marine
Available: In Stock
10375.0000
9800.00
Each
Quantity:
Quantity Price
1 9800.00
8M0176859

Mercury Racing Lower Unit and Gearcase

Mercury Racing 8M0176859 5.44 Inch XL Gearcase

Mercury Racing 8M0176859 is a 5.44 inch XL gearcase assembly with a 1.60 gear ratio and standard rotation. It is used on Mercury Racing 450R supercharged 4.6L V8 Verado platform applications.

This current Mercury Racing gearcase supersedes 8M0159651. Because complete lower unit assemblies are highly specific to shaft length, gear ratio, rotation, engine family, and serial number, confirm your exact application before ordering.

Compatible Applications

Brand Engine / System Application Fitment Note
Mercury Racing 450R Supercharged 4.6L V8 5.44 inch XL gearcase, 1.60 ratio, standard rotation Verify by serial number, shaft length, ratio, and rotation
Mercury Racing High-Horsepower 4.6L V8 Performance Models Select applications requiring XL shaft and 1.60 standard rotation gearcase Confirm the OEM parts diagram for your engine serial number

Important Fitment Note

Always confirm compatibility using your engine serial number, model, existing gearcase number, shaft length, gear ratio, and rotation before ordering. XL, counter rotation, standard rotation, and ratio differences are not interchangeable.

OEM & Cross Reference Numbers

Current Mercury Racing OEM Number 8M0176859
Superseded From 8M0159651
Description 5.44 inch XL gearcase, 1.60 ratio, standard rotation

What This Part Is Used For

This is a complete lower unit gearcase assembly used to transfer engine power through the driveshaft and gear set to the propeller shaft. The 1.60 gear ratio and standard rotation configuration are designed for specific Mercury Racing performance setups.

Replacement may be required after gearcase impact damage, internal gear failure, bearing damage, housing damage, or a complete lower unit service decision where assembly replacement is preferred over rebuilding.

Key Features and Benefits

  • Genuine Mercury Racing gearcase assembly
  • Current part number 8M0176859
  • Supersedes Mercury Racing 8M0159651
  • 5.44 inch gearcase for high-performance applications
  • XL shaft configuration
  • 1.60 gear ratio with standard rotation
  • Designed for select Mercury Racing 450R and 4.6L V8 performance models
  • Best verified by serial number, shaft length, ratio, and rotation

FAQ

What does Mercury Racing 8M0176859 replace?

Mercury Racing 8M0176859 supersedes 8M0159651 for this 5.44 inch XL, 1.60 ratio, standard rotation gearcase application.

Does this fit the Mercury Racing 450R?

This gearcase is used on Mercury Racing 450R supercharged 4.6L V8 applications that require the XL shaft, 1.60 gear ratio, and standard rotation gearcase.

Is this the same as a counter rotation gearcase?

No. This page is for the standard rotation version. Counter rotation gearcases use different part numbers and must be matched to the correct engine and boat setup.

What should I verify before ordering?

Verify your engine serial number, shaft length, rotation, gear ratio, and current gearcase part number. Complete gearcase assemblies are application specific and should not be selected by horsepower alone.

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  • Typical delivery time is 1-5 business days.

30-Day Return Policy

  • Returns accepted within 30 days of delivery.
  • Parts must be new, unused, and in original packaging.
  • Installed parts are not returnable.
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Searchable Terms

Mercury Racing 450R gearcase, Mercury 450R lower unit, Mercury Racing XL gearcase, 5.44 inch gearcase, 1.60 ratio Mercury gearcase, Mercury standard rotation gearcase, Mercury V8 Racing lower unit, 450R standard rotation lower unit

Searchable Part Numbers

8M0176859, 8M0159651, Mercury Racing 8M0176859, Mercury Racing 8M0159651

Non-Stock

OEM or Aftermarket
OEM
Manufacturer
Mercury