MERCURY GRAND MARQUIS Differential & Rear-End Components

Differential, Eaton Detroit Truetrac, Limited Slip, 31-Spline, Ford, 8.8 in., Each

Part Number: ETN-913A561

4.86 out of 5 stars ( 28 )

Estimated Ship Date: Monday 12/1/2025

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• $75 Summit Bucks

Differential, Eaton Detroit Truetrac, 31-Spline, Ford 9 in., Each

Part Number: ETN-913A586

4.75 out of 5 stars ( 12 )

Estimated Ship Date: Monday 12/1/2025

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• $75 Summit Bucks

Gear, Ring and Pinion, 3.89:1 Ratio, Ford, 9 in., Set

Part Number: RMG-79-0043-1

5.0 out of 5 stars ( 2 )

Estimated Ship Date: Monday 12/1/2025

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Gear, Ring and Pinion, 4.29:1 Ratio, Ford, 9 in., Set

Part Number: RMG-79-0079-1

5.0 out of 5 stars ( 1 )

Estimated Ship Date: Monday 12/1/2025

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Gear, Ring and Pinion, 4.11:1 Ratio, Ford, 9 in., Set

Part Number: RMG-79-0045-1

5.0 out of 5 stars ( 3 )

Estimated Ship Date: Monday 12/1/2025

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Differential, Eaton Detroit Truetrac, 28-Spline, Ford, 8.8 in., Each

Part Number: ETN-912A562

5.0 out of 5 stars ( 5 )

Estimated Ship Date: Monday 12/1/2025

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• $75 Summit Bucks

Gear, Ring and Pinion, 4.57:1 Ratio, Ford, 9 in., Set

Part Number: RMG-79-0080-1

5.0 out of 5 stars ( 1 )

Estimated Ship Date: Monday 12/1/2025

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Gear, Pro Ring and Pinion, 3.70:1 Ratio, Ford, 9 in., Set

Part Number: RMG-79-0004-1

5.0 out of 5 stars ( 3 )

Estimated Ship Date: Monday 12/1/2025

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Ring and Pinion Gears, 4.88:1 Ratio, Standard Ring Gear Rotation, Ford 8.8 in., Set

Part Number: MGR-F8-8-488

5.0 out of 5 stars ( 2 )

Estimated Ship Date: Monday 12/1/2025

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Gear, Ring and Pinion, 4.30:1 Ratio, Ford, 9 in., Set

Part Number: MGR-F890430

5.0 out of 5 stars ( 3 )

Estimated Ship Date: Monday 12/1/2025

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Gear, Ring and Pinion, 4.86:1 Ratio, Ford, 9 in., Set

Part Number: RMG-79-0066-1

Not Yet Reviewed

Estimated Ship Date: Monday 12/1/2025

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Gear, Ring and Pinion, 4.88:1 Ratio, Ford, 8.8 in., Set

Part Number: RMG-6903821

5.0 out of 5 stars ( 1 )

Estimated Ship Date: Monday 12/1/2025

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Gear, Pro Ring and Pinion, 3.60:1 Ratio, Ford, 9 in., Set

Part Number: RMG-7900031

Not Yet Reviewed

Estimated Ship Date: Monday 12/1/2025

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Gear, Ring and Pinion, 6.20:1 Ratio, Ford, 9 in., Set

Part Number: RMG-79-0023-1

Not Yet Reviewed

Estimated Ship Date: Dec 18, 2025 if ordered today

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• Special Order

Differential Carrier, Limited Slip, Ford 8.8 in., 31 Spline, Each

Part Number: YGA-20069

Not Yet Reviewed

Estimated Ship Date: Monday 12/1/2025

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Gear, Ring and Pinion, 4.30:1 Ratio, Ford, 8.8 in., Set

Part Number: RMG-6903761

5.0 out of 5 stars ( 2 )

Estimated Ship Date: Monday 12/1/2025

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Ring and Pinion Gears, Pro Series, 3.70:1 Ratio, Ford 9 in., Set

Part Number: MGR-F990370BP

5.0 out of 5 stars ( 1 )

Estimated Ship Date: Monday 12/1/2025

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Differential Carrier, Positraction, Nodular Iron, Ford 8.8 in., 28 Spline, Each

Part Number: SUM-730942

Not Yet Reviewed

Estimated Ship Date: Monday 12/1/2025

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Gear, Ring and Pinion, 6.50:1 Ratio, Ford, 9 in., Set

Part Number: RMG-79-0054-1

5.0 out of 5 stars ( 1 )

Estimated Ship Date: Monday 12/1/2025

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Gear, Ring and Pinion, 5.83:1 Ratio, Ford, 9 in., Set

Part Number: RMG-79-0019-1

5.0 out of 5 stars ( 2 )

Estimated Ship Date: Monday 12/1/2025

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Differential, Grip LS Traction System, 31-Spline, Ford, 9 in., Each

Part Number: PWT-LS109031

Not Yet Reviewed

Estimated Ship Date: Monday 12/1/2025

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• Mfr. Rebate

$35.00 Mail-In Rebate

Price after Manufacturer Rebate: $701.99

Rebate Expires: 12/31/2025

Get $35 back after rebate on this Powertrax Product! Go to https://www.richmondgear.com/rebate.pdf for details. ...Read More

Get UP TO $55 back after rebate on select Powertrax Products! Go to https://www.richmondgear.com/rebate.pdf for details. Valid on purchases made between 11/1/25 and 12/31/25. Claims must be submitted within 30 days of purchase. Allow 6-8 weeks for processing. Valid in USA and Canada. Limit two qualifying purchases per household or address. This offer cannot be combined with other discounts or offers. Rebate intended for end consumer only. Show Less

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Differential, No-Slip Traction System, 28-Spline, Ford, 9 in., Each

Part Number: PWT-92-0690-2800

Not Yet Reviewed

Estimated Ship Date: Monday 12/1/2025

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• Mfr. Rebate

$40.00 Mail-In Rebate

Price after Manufacturer Rebate: $582.99

Rebate Expires: 12/31/2025

Get $40 back after rebate on this Powertrax Product! Go to https://www.richmondgear.com/rebate.pdf for details. ...Read More

Get UP TO $55 back after rebate on select Powertrax Products! Go to https://www.richmondgear.com/rebate.pdf for details. Valid on purchases made between 11/1/25 and 12/31/25. Claims must be submitted within 30 days of purchase. Allow 6-8 weeks for processing. Valid in USA and Canada. Limit two qualifying purchases per household or address. This offer cannot be combined with other discounts or offers. Rebate intended for end consumer only. Show Less

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Ring and Pinion Gears, Ford 8.8 in., 3.73:1 Ratio, 30-Spline, Standard Rotation, Installation Kit Included, Kit

Part Number: YGA-10618

4.0 out of 5 stars ( 2 )

Estimated Ship Date: Dec 29, 2025 if ordered today

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• Special Order

Gear, Ring and Pinion, 5.67:1 Ratio, Ford, 9 in., Set

Part Number: RMG-79-0007-1

Not Yet Reviewed

Estimated Ship Date: Monday 12/1/2025

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