Crate Engines

SoCal Diesel

Billet main girdle for use with 2017-2023 Duramax 6.6L L5P engines

$864.00

SKU: S06O L5PBILLETMAINGIRDLE

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Special Order
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Non-Returnable Item

Description

The SoCal Diesel L5PBILLETMAINGIRDLE is a billet main girdle for the L5P Duramax engine. It reinforces the main caps to prevent movement at high power levels, addressing a known issue with main cap flexing. This part requires a separate SoCal Diesel main stud kit for installation.

Fitment

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Specifications

BrandSoCal Diesel
Part NumberS06O L5PBILLETMAINGIRDLE

Videos

1200HP Duramax Engine Build |EP1| Parts Overview

1200HP Duramax Engine Build |EP1| Parts Overview

Buy with Confidence

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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