Drivetrain› Differentials and Rear-End Components

Eaton

GM BEVEL SET 12B CAR 3.31 SUPERFINISH

$558.99

SKU: E00K ESF01888331

Special Order
Special Order
Ships in 4–6 weeks
Free Shipping over $200
$100 Minimum Order
Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Overview

Eaton Street Series ring and pinion sets are centered on high performance for enthusiasts. Street Series sets are made from high-quality 8620 or 4320 steel providing long life under daily-use conditions. They are available in a wide range of axle ratios for many applications and can be ordered with their patented Super Finish process, eliminating the need for break-in. For your spirited traction needs, choose Eaton Street Series ring and pinion sets. Features may include: Made from high-quality 8620 or 4320 steel for long life, CNC-cut teeth for reduced stress and smooth engagement, Computer-controlled heat-treat for durability, Rolled splines for added tooth strength, Patented Super Finish process is optional–gives the gears a highly polished look, reduces friction and wear, improves oil retention, and eliminates the need for break-in. Up to a 3 to 5 percent more horsepower can be achieved through reduced friction losses. Item Description – GM BEVEL SET 12B CAR 3.31 Product Category – Ring & Pinion Super Finish Spline Count – 30
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GM BEVEL SET 12B CAR 3.31 SUPERFINISH

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

BrandEaton
Part NumberE00K ESF01888331

Videos

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GM 12-Bolt rear diff UPGRADE: Positraction and gear swap | Hagerty DIY
GM 12 bolt Ring and Pinion Install with Summit Racing LImited Slip

GM 12 bolt Ring and Pinion Install with Summit Racing LImited Slip
Selecting a Ring and Pinion Gear Set for Your Vehicle

Selecting a Ring and Pinion Gear Set for Your Vehicle

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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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