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Flywheel Bell Housing 3937426 3903282 4947579 forCummins 4B 4BT 4BTA 6B 6BT 6BTA
$793.99
Sale price
$793.99
Regular price
Available to Order
Designed for select Cummins diesel engines and compatible equipment, this aftermarket flywheel bell housing helps restore the structural connection between the engine and transmission.
Not sure which part fits your equipment?
Our Northline Parts team can help you find the right replacement. Support Hours: Monday–Friday, 8:00 AM–5:00 PM CT | Live Chat: Available 24/7
I reached out for some replacement head bolts and they responded quickly with a few questions and cautionary information and is sending me some bolts. Great customer service! Thanks
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Product Overview
The bell housing surrounds the flywheel area and aligns the engine with the transmission or driven equipment. Cracks, damaged threads, worn mounting surfaces, or impact damage can make replacement necessary.
Replacement references include 3937426, 3903282, 4947579. Compare the part number, engine family, transmission pattern, starter location, mounting holes, and housing depth before ordering.
Key Features & Performance
- Designed for compatible Cummins engine applications
- Requires accurate alignment during installation
- Restores the engine-to-transmission mounting structure
- Protects the flywheel and coupling area
Fitment & Compatibility
Compatible with Cummins 4B, 4BT, 4BTA, 6B, 6BT, and 6BTA engine applications. Serial-number breaks, production changes, or equipment options may affect the required part.
Technical Specifications
- Product Type: Flywheel Bell Housing
- Compatible Brand: Cummins
- Part Number(s): 3937426, 3903282, 4947579
Frequently Asked Questions
Q: Can a bell housing be selected by engine family alone? A: No. Match the part number, transmission pattern, starter location, depth, and all mounting features with the original housing.
Q: Is this an original OEM part? A: No. It is an aftermarket component made to replace the listed part in compatible equipment.
Confirm the original part number and physical configuration before ordering, especially when multiple versions were used.