Engines and Components› Engines, Blocks and Components

Chevrolet Performance

3.6L 6-Cylinder Engine Assembly

$800.00

SKU: 12678996

In Stock
In Stock
Ships by Sep 13
Free Shipping over $200
$100 Minimum Order
30 Days Return
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Overview

The Chevrolet Performance 12678996 is a 3.6L 6-cylinder engine assembly designed for various GM vehicles. This engine features a sand cast aluminum block with cast-in iron bore liners and a hardened forged steel crankshaft. It produces 321 horsepower at 6800 RPM and 275 ft-lbs of torque at 4900 RPM.

This genuine GM part is engineered and tested to rigorous standards. It requires programming and/or special setup procedures as outlined in GM Service Information to ensure proper operation.
Show original supplier description
The Chevrolet Performance 12678996 is a 3.6L 6-cylinder engine assembly, a direct replacement for many 2010-2017 Chevrolet, Cadillac, and Buick cars and SUVs. This all-aluminum engine is built with a sand cast aluminum block featuring cast-in iron bore liners and a 3.780" bore, paired with a hardened forged steel crankshaft and cast aluminum DOHC heads with 66cc combustion chambers. It delivers a robust 321 horsepower at 6800 RPM and 275 ft-lbs of torque at 4900 RPM, with a 11.5:1 compression ratio. This engine assembly is designed for most LFX applications with specific engine codes, including (LH, LJ, GX, GY, GZ, WB, WC19, GT, GB, GC, GD, GE, NG, W). It is important to verify the correct engine code for your vehicle by contacting a technical department with your VIN. The product requires programming and/or special setup procedures, as detailed in GM Service Information, to guarantee its proper operation within the vehicle. This GM Genuine Part is designed, engineered, and tested to rigorous standards and is backed by General Motors with a minimum 12-month warranty. It is crucial to note that this engine is not intended for marine usage. Additionally, some components from the original engine may need to be transferred to the new assembly for complete installation; please verify this before proceeding with installation.

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

BrandChevrolet Performance
Part Number12678996
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.

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