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1978 PONTIAC FIREBIRD Differential & Rear-End Components

Individual Parts

Results 1 - 25 of 43

Differential, Eaton Detroit Truetrac, 28-Spline, GM, 8.5 in., Rear, Each

Part Number: ETN-912A556

4.84 out of 5 stars ( 31 )

Estimated Ship Date: Monday 10/20/2025

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Estimated Ship Date: Monday 10/20/2025

Dura Grip Positraction Carrier, Traction-Loc, GM 7.5/7.6 in., 26 Spline, 3.23 Up Ratio, Each

Part Number: YGA-26017

4.4 out of 5 stars ( 5 )

Estimated Ship Date: Monday 10/20/2025

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Estimated Ship Date: Monday 10/20/2025

Dura Grip Positraction Carrier, Traction-Loc, GM 7.5/7.6 in., 28 Spline, 3.23 Up Ratio, Each

Part Number: YGA-26018

4.2 out of 5 stars ( 5 )

Estimated Ship Date: Monday 10/20/2025

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Estimated Ship Date: Monday 10/20/2025

Differential, Eaton Detroit Truetrac, 26-Spline, GM, 7.5 in., 3.23 and Higher, Each

Part Number: ETN-911A319

5.0 out of 5 stars ( 10 )

Estimated Ship Date: Monday 10/20/2025

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Estimated Ship Date: Monday 10/20/2025

Differential, Posi Performance, Limited Slip, 28-Spline, GM, 8.5 in., 3 Series, Each

Part Number: ETN-19557-010

4.73 out of 5 stars ( 15 )

Estimated Ship Date: Monday 10/20/2025

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Estimated Ship Date: Monday 10/20/2025

Differential, Eaton Detroit Truetrac, 26-Spline, GM, 7.5 in., 3:08 and Down, Each

Part Number: ETN-911A415

5.0 out of 5 stars ( 4 )

Estimated Ship Date: Monday 10/20/2025

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Estimated Ship Date: Monday 10/20/2025

Gear, Ring and Pinion, 3.42:1 Ratio, GM, 8.5/8.6 in., 10-Bolt, 3 Series, Set

Part Number: RMG-4902781

5.0 out of 5 stars ( 9 )

Estimated Ship Date: Monday 10/20/2025

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Estimated Ship Date: Monday 10/20/2025

Differential Carrier, Positraction, Nodular Iron, GM 7.5/7.6 in., 26 Spline, 3.23 Up Ratio, Each

Part Number: SUM-730958

4.33 out of 5 stars ( 6 )

Estimated Ship Date: Monday 10/20/2025

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Estimated Ship Date: Monday 10/20/2025

Differential Carrier, Positraction, Nodular Iron, GM 7.5/7.6 in., 28 Spline, 3.23 Up Ratio, Each

Part Number: SUM-730960

5.0 out of 5 stars ( 1 )

Estimated Ship Date: Monday 10/20/2025

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Estimated Ship Date: Monday 10/20/2025

Gear, Ring and Pinion, 3.90:1 Ratio, GM, 8.5/8.6 in., 10-Bolt, 3 Series, Set

Part Number: RMG-4900341

4.67 out of 5 stars ( 9 )

Estimated Ship Date: Monday 10/20/2025

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Estimated Ship Date: Monday 10/20/2025

Differential, Posi Performance, Limited Slip, 26-Spline, GM, 7.5 in., Each

Part Number: ETN-19663-010

3.0 out of 5 stars ( 2 )

Estimated Ship Date: Monday 10/20/2025

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Estimated Ship Date: Monday 10/20/2025

Gear, Ring and Pinion, 3.73:1 Ratio, GM, 7.5 in., Set

Part Number: MGR-GM75-373

Not Yet Reviewed

Estimated Ship Date: Monday 10/20/2025

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Estimated Ship Date: Monday 10/20/2025

Gear, Ring and Pinion, 4.30:1 Ratio, GM, 8.5/8.6 in., Set

Part Number: MGR-G885430

5.0 out of 5 stars ( 3 )

Estimated Ship Date: Monday 10/20/2025

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Estimated Ship Date: Monday 10/20/2025

Gear, Ring and Pinion, 4.56:1 Ratio, GM, 8.5/8.6 in., 10-Bolt, 3 Series, Set

Part Number: RMG-6901671

2.67 out of 5 stars ( 3 )

Estimated Ship Date: Monday 10/20/2025

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Estimated Ship Date: Monday 10/20/2025

Gear, Ring and Pinion, 3.08:1 Ratio, GM, 8.5/8.6 in., 10-Bolt, 3 Series, Set

Part Number: RMG-4900171

4.67 out of 5 stars ( 3 )

Estimated Ship Date: Monday 10/20/2025

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Estimated Ship Date: Monday 10/20/2025

Gear, Ring and Pinion, 3.73:1 Ratio, GM, 7.5 in./7.625 in., 10-Bolt, 3 Series, Set

Part Number: RMG-4900461

4.86 out of 5 stars ( 7 )

Estimated Ship Date: Monday 10/20/2025

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Estimated Ship Date: Monday 10/20/2025

Ring and Pinion Gear, 2.73:1 Ratio, GM 8.5/8.6, 10 Bolt Cover, 30 Spline, 10 Ring Gear Bolts, Buick, Chevrolet, GMC, Oldsmobile, Pontiac, Set

Part Number: YGA-24490

Not Yet Reviewed

Estimated Ship Date: Nov 18, 2025 if ordered today

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Estimated Ship Date: Nov 18, 2025 if ordered today

Ring and Pinion Gears, 3.90:1 Ratio, 30-spline, Standard Ring Gear Rotation, GM 8.5 in., GM 8.6 in., Set

Part Number: YGA-24159

5.0 out of 5 stars ( 3 )

Estimated Ship Date: Monday 10/20/2025

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Estimated Ship Date: Monday 10/20/2025

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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Estimated Ship Date: Monday 10/20/2025

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

Part Number: YGA-24482

Not Yet Reviewed

Estimated Ship Date: Nov 18, 2025 if ordered today

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Estimated Ship Date: Nov 18, 2025 if ordered today

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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Estimated Ship Date: Monday 10/20/2025

Differential, Grip LS Traction System, 28-Spline, GM, 8.5 in., Each

Part Number: PWT-LS201028

Not Yet Reviewed

Estimated Ship Date: Monday 10/20/2025

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Estimated Ship Date: Monday 10/20/2025

Ring and Pinion Gears and Installation Kit, 8.5" GM 3.73 REAR R&P GEAR/ INSTALL KIT PACKAGE with AK 1563 AXLE BRGS (2.25" OD)

Part Number: YGA-12622

Not Yet Reviewed

Estimated Ship Date: Nov 19, 2025 if ordered today

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Estimated Ship Date: Nov 19, 2025 if ordered today

Gear, Ring and Pinion, 3.73:1 Ratio, 1.438 in. Pinion, 27 Spline, 7.500 in. Ring Gear, GM 7.5/7.6 in., Set

Part Number: YGA-24146

5.0 out of 5 stars ( 1 )

Estimated Ship Date: Monday 10/20/2025

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Estimated Ship Date: Monday 10/20/2025

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