Drivetrain› Differentials and Rear-End Components

Auburn Gear

GM 12 BLT 4 SER CAR 4.10&UP 30T 65-

$525.40

SKU: A027 546031

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

SAME DAY SHIPPING (if ordered before 2pm EST) Auburn Grip-N-Loc Differential. Application: GM 12 Bolt 4-Series. Ring Gear Diameter: 8.875″. Carrier: 4 – Series (4.10:1 and numerically higher). Side Gear Spline: 30 Teeth. Model Years: 1964-1972. Bearing Cone: LM603049. Bearing Cup: LM603012. NEW Grip-N-Loc™ Limited Slip Differential: Built to exceed your expectations. Welcome to Auburn Gear’s most advanced limited slip differential, the Grip-N-Loc™. It builds upon exclusive technologies previously found in our limited slip line, but is even more robust to satisfy the extreme demands of serious drivers. If you push the limits of performance and traction, perhaps through competition, or simply through extreme weather driving, Grip-N-Loc™ is your best choice.
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GM 12 BLT 4 SER CAR 4.10&UP 30T 65-

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

BrandAuburn Gear
Part NumberA027 546031
5,000+ Trusted brands
1M+ Enthusiasts
5M+ Parts sold
(760) 282-4645 hello@motormia.co

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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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