Engines and Components› Crankshafts and Components

Eagle Specialty Products

4340 Forged Steel Crankshaft

$985.99

SKU: EAG434040006123

In Stock
In Stock
Ships by Sep 9
Free Shipping over $200
$100 Minimum Order
30 Days Return
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Overview

The Eagle Specialty Products 434040006123 is a crankshaft designed for high performance applications. It features a 4.000 in. stroke and is constructed from forged 4340 steel. This crankshaft is internally balanced and uses a 2-piece rear main seal.
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The Eagle Specialty Products 434040006123 is a forged 4340 steel crankshaft engineered for high-performance applications. This crankshaft features a 4.000-inch stroke and internal balancing, making it a robust choice for engine builds. Constructed from durable 4340 steel, this crankshaft undergoes a multi-stage heat-treatment process, is stress-relieved, and shot-peened for enhanced strength and longevity. The design includes chamfered oil holes for improved lubrication, a .125-inch radius on rod and main journals to increase strength, and precision-ground, micro-polished journals to less than 5 R.A. To minimize balancing time, a target bob weight of +/- 2 percent is utilized. This crankshaft requires narrow bearings and is designed for a 2-piece rear main seal. It is sold individually.

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.

Fitment

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Specifications

BrandEagle Specialty Products
Part NumberEAG434040006123
CategoryEngines and Components

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Returns & Fitment

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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Shipping

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.

Free shipping over $200 in the continental US. Alaska, Hawaii, U.S. territories (Puerto Rico, U.S. Virgin Islands, Guam, American Samoa, and the Northern Mariana Islands), and international orders carry surcharges — most appear at checkout. Some exceptions (LTL freight, or suppliers who quote freight only after we place the order) won’t. In those cases we’ll reach out with the exact charge before your order moves forward.

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