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Usa Standard Gear

USA Standard Gear Ring and Pinion Sets ZG GM8.5-390 Gear, 3.90:1 Ratio, GM, 8.5 in./8.6 in., Rear, Set

SKU: SPZGM8.5-390

Ring and Pinion Gears
USA Standard Gear Ring and Pinion Sets ZG GM8.5-390 Gear, 3.90:1 Ratio, GM, 8.5 in./8.6 in., Rear, Set

Usa Standard Gear

USA Standard Gear Ring and Pinion Sets ZG GM8.5-390 Gear, 3.90:1 Ratio, GM, 8.5 in./8.6 in., Rear, Set

SKU: SPZGM8.5-390

Ring and Pinion Gears
A$1,073.19
BACKORDER This item will be special ordered in for you. Contact us prior to purchase if you require an ETA.
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Description

IMPORTANT NOTICE: Must use 2.73:1 or numerically higher ratio carrier.

USA Standard Gear ring and pinion sets are high-quality and precision-machined replacements. They're offered for a wide variety of common and hard-to-find applications, differential case designs, and ratios. The right choice adds confidence to your install; select the USA Standard ring and pinion set recommended for your vehicle.

Part Type

Ring and Pinion Gears

Data: v4.2 - Upd: 2026-10-16 00:14:22

Specifications

Product Attributes - Brand
USA Standard Gear
Product Attributes - Manufacturer's Part Number
ZG GM8.5-390
Product Attributes - Part Type
Ring and Pinion Gears
Product Attributes - Product Line
USA Standard Gear Ring and Pinion Sets
Product Attributes - UPC
883584362159
Product Attributes - Differential Case Design Type
GM 8.5/8.6 in.
Product Attributes - Ring and Pinion Ratio
3.90:1
Product Attributes - Cover Bolts
10
Product Attributes - Ring Gear Bolts
10
Product Attributes - Pinion Spline Count
30
Product Attributes - Ring Gear Rotation
Standard
Product Attributes - Ring Gear Teeth
39
Product Attributes - Pinion Gear Teeth
10
Product Attributes - Ring Gear Diameter (in.)
8.500 in.
Product Attributes - Pinion Shaft Diameter (in.)
1.626 in.
Product Attributes - Installation Kit Included
No
Product Attributes - Cover Gasket Included
No
Product Attributes - Pinion Shims Included
No
Product Attributes - Carrier Shims Included
No
Product Attributes - Crush Sleeve Included
No
Product Attributes - Pinion Seal Included
No
Product Attributes - Pinion Nut Included
No
Product Attributes - Ring Gear Bolts Included
No
Product Attributes - Head Bearing Included
No
Product Attributes - Tail Bearing Included
No
Product Attributes - Carrier Bearings Included
No
Product Attributes - Axle Seals Included
No
Product Attributes - Axle Bearings Included
No
Product Attributes - Differential Cover Included
No
Product Attributes - Differential Oil Included
No
Product Attributes - Friction Modifier Included
No
Product Attributes - Installation DVD Included
No
Product Attributes - Quantity
Sold as a set.
Product Attributes - Notes
Must use 2.73:1 or numerically higher ratio carrier.

Reference Information

Brand Name/s Usa Standard Gear
StreetFX SKU spzGM8.5-390
SFX Item ID 4897996
Supplier Item Code 4897996
Manufacturer SKU GM8.5-390
Manufacturer UPC N/A
Alternative References SPZ-36215, in./8.6

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