Product Description
Genuine Federal Mogul 4281M-10 Main Bearing Set (NORS)
This genuine Federal Mogul 4281M-10 Main Bearing Set is a premium New Old Replacement Stock (NORS) component, specifically engineered for the Oldsmobile-manufactured Small Block V8 engine family. Manufactured in the USA, these .010" undersize bearings provide the high-load durability and precise oil clearances required for a professional rebuild of displacements including the 260, 307, 350 (Olds "R" code), and 403 cubic inch power plants. This set is essential for restorations where the crankshaft journals have been professionally ground to .010" undersize, ensuring proper rotational alignment and optimal oil pressure for long-term reliability. It is a direct fit for 1975–1982 GM passenger cars across the Oldsmobile, Buick, and Pontiac lines that utilized Oldsmobile-sourced engines.
Key Features:
- Brand: Federal Mogul
- Part Number: 4281M-10
- Position: Crankshaft Main Bearings
- Size: .010" Undersize
- Engine Fitment: Oldsmobile 260 / 307 / 350R / 403 V8
- Standard Journal Diameter: 2.4983" / 2.4993"
- Origin: Made in the USA
- Condition: NORS (New Old Replacement Stock)
Verified Engine Application Breakout:
| Engine Displacement | Year Range | Vehicle Applications | Notes |
|---|---|---|---|
| 260 ci (4.3L) | 1975–1982 | Oldsmobile | Small Block V8 |
| 307 ci (5.0L) | 1980–1982 | Olds, Buick, Pontiac | Small Block V8 |
| 350 ci (5.7L) | 1968–1980 | Olds, Buick, Pontiac | "R" Code Only; Excludes Diesel |
| 403 ci (6.6L) | 1977–1979 | Olds, Buick, Pontiac | Small Block V8 |
Fits Years:
1968 1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980 1981 1982
Technical Identification Note: For 350ci applications, this set fits the Oldsmobile-sourced gasoline engine (VIN code R) only. It will not fit the Chevrolet-sourced 350L or the Oldsmobile Diesel (350N).
Note on Stock Photos: Due to our inventory of multiple identical units for this specific part number, we utilize representative stock photos for this listing. You will receive a component that strictly meets all listed specifications and fitment requirements. Please be aware that because these are vintage parts, minor cosmetic variations—such as surface finish, color, or production markings—may exist between different manufacturing runs. These slight aesthetic differences are a result of historical production processes and do not impact the part's integrity, performance, or authenticity.
A Note on Fitment Accuracy: We manually research and cross-reference our fitment data using vintage manufacturer catalogs. While we strive for 100% accuracy, these decades-old resources—and the humans reading them—can occasionally contain errors. Additionally, these parts may fit other vehicles and years not explicitly listed in our data. To ensure a seamless restoration, we kindly ask that you perform your own due diligence and verify that this specific part number is correct for your application prior to purchase.
Unbeatable Prices & Expectations
While many of our vintage parts were manufactured decades ago, they remain unused and high-quality. Some original boxes may show signs of shelf-wear, such as dust, tape, or surface distress from years of storage. Rest assured, the components inside have been inspected to ensure they are complete and ready to help you finish your project without breaking the bank.
