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Engines and Components› Pistons and Piston Rings

Cummins

B Series Piston Body

Name: B Series Piston Body
Brand: Cummins
SKU: 3972880

$356.97 $335.80 Save $21.17

SKU: 3972880

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Overview

The Cummins 3972880 is a piston body designed for B series engines. FP Diesel offers a complete range of premium engine and sealing components for commercial, heavy-duty diesel engines, utilizing cutting-edge metallurgy and specialized coatings.

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The Cummins 3972880 is a piston body without a pin, designed as a direct replacement for B series engines. The design addresses the unique challenges of high-load, high-temperature environments. This piston body is part of FP Diesel's comprehensive offering of premium engine and sealing components for commercial and heavy-duty diesel engines. They utilize advanced metallurgy and specialized coatings to ensure performance under strenuous conditions. The parts are engineered specifically for aftermarket repair environments and undergo rigorous validation for fit, form, and function, ensuring a repair you can trust. This part replaces Cummins part numbers 3972880, FP-3972880, and FP3972880. It is compatible with various Cummins engines including ISB, ISB5.9 CM800, ISBE, ISBE4 CM850, ISD4.5 CM2150 SN, and QSB.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

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Specifications

Brand	Cummins
Part Number	3972880
Category	Engines and Components

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Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

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