1978 PONTIAC FIREBIRD Differential & Rear-End Components

Gear, Ring and Pinion, 3.90:1 Ratio, GM, 8.5/8.6 in., 10-Bolt, Set

Part Number: MGR-GM10-390

3.0 out of 5 stars ( 2 )

Estimated Ship Date: Monday 10/20/2025

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Ring and Pinion Gears, 3.42:1 Ratio, 30-spline, Standard Ring Gear Rotation, GM 8.5/8.6 in., Set

Part Number: SPZ-36213

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Estimated Ship Date: Nov 4, 2025 if ordered today

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Differential Carrier Rebuild Kits and Spider Gears, GM 8.5 in., Side Gears, 28-spline, 10-bolt, Buick, Chevrolet, GMC, Oldsmobile, Pontiac, Kit

Part Number: SPZ-39026

5.0 out of 5 stars ( 1 )

Estimated Ship Date: Monday 10/20/2025

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Gear, Ring and Pinion, 4.88:1 Ratio, GM, 8.5/8.6 in., 10-Bolt, 3 Series, Set

Part Number: RMG-6901691

4.6 out of 5 stars ( 5 )

Estimated Ship Date: Monday 10/20/2025

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Crate Axle, 70-81 GM Camaro/F-Body Centurion 9-Inch, Black PC, 31-Spline, 4.11 Ratio, Helical Limited Slip, Wilwood 11" Dynapro Black Calipers

Part Number: CUR-CR-GF341TWAB

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Estimated Ship Date: Monday 10/20/2025

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Cross Pin, GM, 10-Bolt, 8.5 in. Each

Part Number: MGR-14006401

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Estimated Ship Date: Monday 10/20/2025

Pinion Nut, Steel, Each

Part Number: YGA-33152

5.0 out of 5 stars ( 2 )

Estimated Ship Date: Monday 10/20/2025

Crush Sleeve, Steel, 0.620 in. Tall, Each

Part Number: YGA-33097

1.0 out of 5 stars ( 1 )

Estimated Ship Date: Monday 10/20/2025

Ring and Pinion-GM 8.5/8.625

Part Number: MGR-GM10-373A

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Estimated Ship Date: Nov 10, 2025 if ordered today

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Differential Cover, 10-bolt, Steel, Chrome, GM 7.5 in., GM 7.625 in., Each

Part Number: YGA-32014

5.0 out of 5 stars ( 1 )

Estimated Ship Date: Monday 10/20/2025

Ring and Pinion Gears, GM 8.5/8.6 in., 4.88:1 Ratio, 30-spline, Standard, Must Use 2.73:1 or Numerically Higher Ratio Carrier, GM 8.5/8.6 in., Set

Part Number: SVL-2023704

5.0 out of 5 stars ( 1 )

Estimated Ship Date: Monday 10/20/2025

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Gear, Ring and Pinion, 3.08:1 Ratio, GM, 7.5 in., Set

Part Number: MGR-GM75-308

3.0 out of 5 stars ( 2 )

Estimated Ship Date: Nov 10, 2025 if ordered today

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Differential Clutch, Steel Pack, Rear, Posi, GM, 8.875 in., Set

Part Number: YGA-16041

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Estimated Ship Date: Nov 18, 2025 if ordered today

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Differential Carrier Bearing, Races Included, Koyo Bearing, Steel, Set

Part Number: MGR-706016XR

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Estimated Ship Date: Monday 10/20/2025

Differential Carrier Bearings, Standard Replacement, Includes Cup, 1.625 in. Bore, AMC, GM, Mopar, Jeep, International, Studebaker, Hummer, Each

Part Number: TMK-SET69

5.0 out of 5 stars ( 1 )

Estimated Ship Date: Monday 10/20/2025

Gear, Ring and Pinion, 3.23:1 Ratio, GM 8.5 in., Set

Part Number: RNB-697-810

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Estimated Ship Date: Monday 10/20/2025

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Ring and Pinion Gears, 4.30:1 Ratio, 27-spline, Standard Ring Gear Rotation, GM 7.5 in., Set

Part Number: YGA-24482

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Estimated Ship Date: Nov 18, 2025 if ordered today

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Ring & Pinion Gear, 5.38 Ratio, GM, 8.5 in./8.6 in., Set

Part Number: YGA-24494

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Estimated Ship Date: Nov 18, 2025 if ordered today

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Differential Cover, Aluminum Girdle Cover, Natural, 10-bolt, GM 8.5 in., GM 8.6 in., Each

Part Number: YGA-32121

1.0 out of 5 stars ( 1 )

Estimated Ship Date: Monday 10/20/2025

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Differential Cross Shaft, Steel, 0.795 in. Diameter, Each

Part Number: YGA-33401

5.0 out of 5 stars ( 1 )

Estimated Ship Date: Monday 10/20/2025

Differential, No-Slip Traction System, 28-Spline, GM, 8.5 in., Each

Part Number: PWT-9207852805

4.5 out of 5 stars ( 4 )

Estimated Ship Date: Monday 10/20/2025

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Pinion Nut Washer, GM, Each

Part Number: YGA-33167

5.0 out of 5 stars ( 2 )

Estimated Ship Date: Monday 10/20/2025

Ring and Pinion Kit

Part Number: RMG-GM75355TK

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Estimated Ship Date: Nov 10, 2025 if ordered today

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Pinion Nut, Steel, Each

Part Number: MGR-1260823

4.0 out of 5 stars ( 5 )

Estimated Ship Date: Monday 10/20/2025

Differential Inner Gear Kit; GM 8.5 - 30 Spline, Open Diff

Part Number: SVL-10020478

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Estimated Ship Date: Nov 3, 2025 if ordered today

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