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ARP Crankshaft

Chromoly Torque-to-Spec Crankshaft Bolt

Name: Chromoly Torque-to-Spec Crankshaft Bolt
Brand: ARP Crankshaft
SKU: 234-2503
Price: 34.99 USD
Availability: InStock

$39.99 $34.99 Save $5.00

SKU: 234-2503

Special Order

Ships in 4–6 weeks

Free Shipping over $200

$100 Minimum Order

30 Days Return

Description

The ARP Harmonic Balancer Bolt (Crank Bolt) for LS & LT Engines is a robust upgrade designed to replace the OEM crankshaft bolt found on GM GEN 3/4 LS and GEN 5 LT engines. It is constructed from high-strength chromoly material with a tensile strength of 200,000 psi, offering significantly greater durability. It is compatible with various LS engine displacements including 4.8L, 5.3L, 5.7L, 6.0L, and 6.2L. However, it is important to note that this part does NOT fit dry sump engine applications. Additionally, it will not fit LS7 engines. The ARP 234-2503 features a 12-point head style that accommodates a deep socket, simplifying installation and reducing the risk of stripping the head. The underhead length is 4.330 inches, and it uses a 16mm x 2.0 thread size. It replaces GM part number 12557840.

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

Brand	ARP Crankshaft
Part Number	234-2503
Category	Engines 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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