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ARP LS

LS Harmonic Balancer Bolt Kit

Name: LS Harmonic Balancer Bolt Kit
Brand: ARP LS
SKU: 234-2503
Price: 34.99 USD
Availability: InStock

$34.99

SKU: 234-2503

In Stock

Ships by Sep 12

Free Shipping over $200

$100 Minimum Order

30 Days Return

Description

The ARP LS Harmonic Balancer Bolt Kit (234-2503) provides a superior replacement for the OEM crankshaft bolt on GM Gen III/IV LS and Gen V LT engines. Constructed from high-strength chromoly material, this bolt boasts a tensile strength of 200,000 psi, significantly exceeding OEM specifications. It features a M16 x 2.0 bolt size, a 4.330" underhead length (UHL), and a convenient 1-1/16" wrenching size. The black oxide finish provides corrosion resistance, and a washer is included for proper installation. This kit is compatible with a wide range of GM LS engines, including 4.8L, 5.3L, 5.7L (LS1, LS6), 6.0L (LQ4, LQ9), and 6.2L (L92, L76, L77, L96) variants. However, it is crucial to note that this bolt kit does NOT fit LS7 engines or dry sump engine applications. It replaces the 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 LS
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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