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King Engine Bearings MB5278AM1.0 Main Bearing Set Ford 2.3L 140ci L4 1.0mm OS

(1991-1993 Ford Mustang; 1989-2001 Ford Ranger; 1996-2000 Ford F-100 Ranger; 1998-2001 Mazda B2500; 1985-1989 Merkur XR4Ti)

Manufacturer

Picture for manufacturer King Engine Bearings

Part Number

MB5278AM1.0
12 reviews
Sale Price

$46.13

Estimated ship date Saturday, November 28

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Product Details

The King Engine Bearings MB5278AM1.0 is a complete main bearing set engineered for Ford 2.3-liter (140ci) inline 4-cylinder engines. This set features a 1.0mm oversized (OS) specification, designed for engines requiring a re-machined or worn crankshaft journal to be restored to proper tolerances.

King Engine Bearings are manufactured to strict OEM dimensional standards, offering reliable sealing, precise crush, and consistent oil film clearances critical for long engine life.

Material & Construction:

  • Bi-Metal Aluminum construction — standard aluminum-based bearing material equivalent to SAE-783
  • Optimized for low to medium load engine applications
  • Provides excellent conformability and embeddability to protect crankshaft journals
  • Corrosion-resistant aluminum alloy overlay for extended service life

Product Specifications:

  • Part Number: MB5278AM1.0
  • Bearing Type: Main Bearing Set
  • Material: Bi-Metal Aluminum (SAE-783 equivalent)
  • Oversize: 1.0mm
  • Engine: Ford 140ci / 2.3L, L4

King Engine Bearings are a trusted choice among professional engine builders and rebuilders worldwide, delivering consistent quality and precision fitment for engine rebuild and overhaul applications.

Products specifications

Fits

1991-1993 Ford Mustang; 1989-2001 Ford Ranger; 1996-2000 Ford F-100 Ranger; 1998-2001 Mazda B2500; 1985-1989 Merkur XR4Ti

Flange Oversize

FL ON MAX

Material

bimetal (aluminum base)

Undersize

1.0

STD Max Thickness

2.423

Shaft UnderSize

1.0mm

Housing Diameter

60.91 / 60.89 mm || 2.398 / 2.397 inch

STD Shaft Diameter

56.03 / 56.01 mm || 2.206 / 2.205 inch

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Site was easy to use, customer services was very pleasant helpful when I needed to information on my order status. Will do business with them again.

Had a hitch that no one seemed to have at a reasonable price.

The only thing I would like to know is what the manifold kit comes with for hardware. Its not specified if they come with any hardware or gaskets at all and i would like to be prepared to do the job when they arrive in the mail.

Really easy and fast

Organized website!

Easy mobile site. Chose 2nd day air. Would love if handling time was 1 business day. We shall see!

My experience with autoplicity was great. Great selection and service. Fast shipping. Will definitely use them again.

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Quick. No hassel. Best prices.

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