1978 Mercury Grand Marquis Differentials

Keep Your 1978 Mercury Grand Marquis in Top Shape with Quality Differentials

Whether you’re repairing or upgrading your Differential, using high-quality parts is key to keeping your 1978 Mercury Grand Marquis looking sharp and performing at its best. At Advance Auto Parts we carry a wide selection of dependable options, including Differential Oil, Differential Pinion Seals, and Rear Differential Cover Gaskets. Whether you’re replacing a damaged part or enhancing your truck’s style and protection, you’ll find exactly what you need to get the job done right.

Top-Rated Differentials from Trusted Brands

Looking for a reliable Differential? We’ve got you covered with options from brands you know and trust like National, Motive Gear, and Powertrax. For example, National Differentials start at just $7.79 with an average 4.3 star rating. Motive Gear and Powertrax offer similar pricing and quality, backed by strong customer feedback. With over 96 reviews and a solid 4 star average, you can shop with confidence knowing other Mercury Grand Marquis owners approve.

Competitive Prices and Extensive Inventory

The average price for a 1978 Mercury Grand Marquis Differential at Advance Auto Parts is around $263.37, with a range that starts at $1.99 and goes up to $1,211.99. With 384 options in stock from 11 trusted brands, finding the right fit is easy. Popular picks like Oil Seal, Cover Bolt For Ford 7.5", 8.8" & 9.75", and Pinion Crush Sleeves start at just $5.99 and offer a great balance of form and function.

Explore Related Parts

While you’re upgrading or replacing your Differential, don’t forget to check out other key components like Drive Shafts and Axles and Universal Joints. At Advance Auto Parts, we’re here to help you keep your 1978 Mercury Grand Marquis in peak condition, inside and out.

Essential 1978 Mercury Grand Marquis Differentials

USA Standard Gear – Master Overhaul Kit for the Ford 9" LM102910 Differential (Part No.37033)

Master Overhaul Kit for the Ford 9" LM102910 Differential

from

$221.99
USA Standard Master Overhaul kits let you finish your install with confidence. This kit uses Koyo bearings and races. Included are carrier bearings and races, pinion bearings and races, pinion seal, complete shim kit, ring gear bolts, pinion nut, crush sleeve (if applicable), oil baffles and slingers (if applicable), threading locking compound, marking compound with brush and gasket.

Product Features:
  • Fits Ford 9″ with LM102910 carrier race
  • Uses Koyo bearings and races
  • Included are carrier bearings and races, pinion bearings and races, pilot bearing, pinion seal, complete shim kit, ring gear bolts, pinion nut, crush sleeve, thread locker, marking compound with brush and gasket.
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Yukon Gear – Chrome Cover For 8.8" Ford (Part No.32009)

Chrome Cover For 8.8" Ford

from

$74.99
Chrome cover for 8.8″ Ford.

Product Features:
  • Fits Ford 8.8″
  • Chrome
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Motive Gear – Nodular Differential Housing (Part No.26325)

Nodular Differential Housing

from

$533.99


Product Features:
  • NODULAR HOUSING 9″ FORD 3.25″ BORE
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Yukon Gear – Pinion Gear And Thrust Washer (0.750" Shaft) For 8.8" Ford (Part No.33297)

Pinion Gear And Thrust Washer (0.750" Shaft) For 8.8" Ford

from

$8.99
Pinion gear thrust washer (0.750″ shaft) for 8.8″ Ford.

Product Features:
  • Pinion gear thrust washer
  • Fits Ford 8.8″
  • 0.750″ I.D.
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Yukon Gear – Trac Loc Steel Clutch Plate, 4 Tab (Part No.16178)

Trac Loc Steel Clutch Plate, 4 Tab

from

$8.99
Product Features:
  • Steel clutch plate
  • Fits Ford 8″ and 9″ Trac Loc
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Yukon Gear – Outer Oil Slinger For Ford 7.5", 8.8", 9", 10.25" (Part No.33022)

Outer Oil Slinger For Ford 7.5", 8.8", 9", 10.25"

from

$8.99
Replacement outer oil slinger for Ford 7.5″, 8.8″, 9″, 10.25″, Nissan Titan rear, Dana 44 Rubicon & 44 JK non-Rubicon.

Product Features:
  • Outer oil slinger for Ford 10.25″, 7.5″, 8.8″ and 9″ also Jeep JK and Nissan Titan rear
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Yukon Gear – 3.062" Side Adjuster For Ford 9" (Part No.32139)

3.062" Side Adjuster For Ford 9"

from

$94.99
3.062″ side adjuster, Only Fits Yukon Ford 9″ Drop Out, new design ONLY.

Product Features:
  • Side adjuster
  • Fits Ford 9″
  • 3.062″ designs only
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Yukon Gear – Trac Loc Clutch Guide For 9" Ford (Part No.33250)

Trac Loc Clutch Guide For 9" Ford

from

$4.99
Trac Loc clutch guide for 9″ Ford.

Product Features:
  • Clutch guide
  • Fits Ford 8″ and 9″
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USA Standard Gear – 9" Ford Spartan Locker Cross Pin, Short (Part No.17022)

9" Ford Spartan Locker Cross Pin, Short

from

$26.99
9″ Ford Spartan locker cross pin, short.

Product Features:
  • USA Standard Gear heavy-duty cross pin shaft
  • Fits Ford 9″
  • Works with Spartan Locker or standard open spider gears
  • Short shaft for four pinion designs
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Yukon Gear – Adjuster Lock Bolt 3.062" & 3.250" Ford 9" Drop Out (Part No.32149)

Adjuster Lock Bolt 3.062" & 3.250" Ford 9" Drop Out

from

$3.99
Adjuster lock bolt 3.062″ & 3.250″ Yukon Ford 9″ Drop Out.

Product Features:
  • Side adjuster lock bolt
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Dorman – Differential Clutch Kit (Part No.697-780)

Differential Clutch Kit

from

$262.99
This differential disc kit is a low-cost, time-saving repair solution for the posi-traction function. They are designed to match the fit and performance of the original disc on specific vehicle years, makes and models.

Product Features:
  • Direct replacement – this differential clutch kit provides the necessary components for repairing the original equipment on specific vehicles
  • Quality materials – all components are built for reliable longevity and performance
  • Smart solution – provides original equipment fit and function for a competitive price compared to original manufacturer
  • Trustworthy quality – backed by team of designers and engineers in the United States
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Yukon Gear – Pinion Support Bolt For 8" And 9" Ford (Part No.33242)

Pinion Support Bolt For 8" And 9" Ford

from

$6.99
Pinion support bolt for 8″ and 9″ Ford.

Product Features:
  • Pinion support bolt for Ford 8″ and 9″
  • 3/8″ x 24 thread
  • 1.0″ long
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Yukon Gear – Super Carrier Shim Kit For Ford 8.8", GM 12 Bolt Car & Truck, 8.6 & Vette (Part No.55002)

Super Carrier Shim Kit For Ford 8.8", GM 12 Bolt Car & Truck, 8.6 & Vette

from

$59.99
Product Features:
  • Super carrier shim kit for Ford 8.8″, GM 12 bolt passenger car and truck, GM 8.0″, 8.6″, 8.6″ IRS and 1963-1979 Corvette
  • Interlocking design makes installation much easier
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Motive Gear – Differential Pinion Solid Spacer Kit w/Shims (Part No.SS9)

Differential Pinion Solid Spacer Kit w/Shims

from

$45.99
All Motive Gear products are engineered for their specific application and manufactured in state of the art facilities. All of our products undergo rigid quality control processes to insure proper fit, performance and longevity. Motive Gear products can be found in the winners circle at NHRA, IHRA, NMRA, NMCA, SODA, SCORE, BITD, Ultra-4 and NASCAR events because we offer unmatched selection and quality demanded by racers and their crew chiefs – the same quality and selection demanded by DIY customers and top mechanics. With four warehouses strategically located across North America, most Motive Gear orders arrive within 2-4 days. Win with Motive Gear!
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Yukon Gear – Tracloc For Ford 9" Wtih 28 Spline Axles – Street Design (Part No.26008)

Tracloc For Ford 9" Wtih 28 Spline Axles - Street Design

from

$789.99
The Yukon Dura Grip provides aggressive yet smooth traction to give you the confidence & performance you need. Get longer life and better traction with the heavy duty Yukon Dura Grip Positraction. The Yukon Trac Loc uses a nodular case, billet side hat, and forged internals for higher strength than stock Trac-Locs. The units use composite clutches for high performance and long life. All units are Rebuildable. Yukon offers a one year warranty against manufacturing defects.

Product Features:
  • Fits Ford 9″ with 28 spline axles
  • Trac Loc positraction
  • Clutch style positraction
  • Street design
  • Internal gears are manufactured using forged 4320 steel and cut to provide stronger teeth
  • Fully rebuildable
  • Assembled in the USA
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Felpro – Differential Carrier Gasket Oval Shaped 10 Bolt Hole Gasket (Part No.RDS 55074)

Differential Carrier Gasket Oval Shaped 10 Bolt Hole Gasket

from

$9.99
Fel-Pro® gaskets are specifically designed for the repair environment to deliver a reliable seal on even the most troublesome applications. Designed for imperfect sealing surfaces and manufactured with proprietary materials, you can count on Fel-Pro for innovative sealing solutions for the real-world repair environment.

Product Features:
  • Meets or exceeds all original equipment specifications
  • Application specific design to ensure a perfect fit
  • Unsurpassed quality you can trust
  • Validated for fit, form and function
  • Each Fel-Pro gasket, no matter how small, is engineered to exacting standards with proprietary design, engineering and manufacturing processes
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Yukon Gear – Purple Aluminum Pinion Support For 9" Ford Daytona (Part No.32036)

Purple Aluminum Pinion Support For 9" Ford Daytona

from

$264.99
Product Features:
  • Fits Ford 9″ with 28 spline pinion
  • Larger inner pinion bearing reduces gear deflection under high load
  • Races installed
  • 6061 aluminum
  • Annodized purple
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Yukon Gear – Pilot Bearing Retainer For Ford 9" (Part No.33255)

Pilot Bearing Retainer For Ford 9"

from

$11.99
Pilot bearing retainer for Ford 9″.

Product Features:
  • Pilot bearing retainer for Ford 9″
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Yukon Gear – Star Washers, 3.062" Ford 9" Drop Out New Design Only (Part No.32143)

Star Washers, 3.062" Ford 9" Drop Out New Design Only

from

$4.99
STAR washers, 3.062″ Yukon Ford 9″ Drop Out new design ONLY.

Product Features:
  • Star washer
  • Fits Ford 9″
  • 3.062″ designs only
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Motive Gear – Differential Master Bearing Kit – Koyo (Part No.R8.8RMK)

Differential Master Bearing Kit - Koyo

from

$126.99
Motive Gear Differential Bearing Kits Include Front & Rear Pinion Bearing, Pinion Seal, Carrier Bearings, Pilot Bearing Where Applicable, Gear Marking Compound, Crush Sleeve, Pinion Nut, Brush, Thread Locking Compound And Cover Gasket Or Rtv

Product Features:
  • KIT BRG&SL FORD MSTR 8.8
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Motive Gear – Differential Pinion Nut (Part No.379570S)

Differential Pinion Nut

from

$6.99
All Motive Gear products are engineered for their specific application and manufactured in state of the art facilities. All of our products undergo rigid quality control processes to insure proper fit, performance and longevity. Motive Gear products can be found in the winners circle at NHRA, IHRA, NMRA, NMCA, SODA, SCORE, BITD, Ultra-4 and NASCAR events because we offer unmatched selection and quality demanded by racers and their crew chiefs – the same quality and selection demanded by DIY customers and top mechanics. With four warehouses strategically located across North America, most Motive Gear orders arrive within 2-4 days. Win with Motive Gear!
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Yukon Gear – Standard Open Carrier Case, Ford 7.5" (Part No.20071)

Standard Open Carrier Case, Ford 7.5"

from

$369.99
Product Features:
  • Standard open carrier case
  • Fits Ford 7.5″
  • Does not include spider gears
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Yukon Gear – 7.5" Ford Cover Gasket (Part No.23009)

7.5" Ford Cover Gasket

from

$9.99
7.5″ Ford cover gasket.

Product Features:
  • Cover gasket
  • Fits Ford 7.5″
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Yukon Gear – Pinion Install Kit For Ford 7.5" Differential (Part No.13039)

Pinion Install Kit For Ford 7.5" Differential

from

$184.99
Yukon Pinion installation kits are a terrific solution for gear installation on lower mileage vehicles where the carrier bearings & races can be reused. This kit uses Timken bearings and races along with a high quality pinion seal and small parts. Included in this kit are the pinion bearings and races, pilot bearing (if applicable), crush sleeve (if applicable), complete pinion shim kit, thread locker, and marking compound with brush. Yukon does extensive research for each application to make sure your kit will arrive with all the correct parts you need to install your pinion gear.

Product Features:
  • Fits Ford 7.5″
  • Included are pinion bearings and races, pinion seal, pinion nut, crush sleeve, complete pinion shim kit, and marking compound with brush.
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Yukon Gear – Side Gear And Thrust Washer (0.875" Shaft) For 8.8" Ford (Part No.33300)

Side Gear And Thrust Washer (0.875" Shaft) For 8.8" Ford

from

$11.99
Side gear thrust washer (0.875″ shaft) for 8.8″ Ford.

Product Features:
  • Side gear thrust washer for Ford 8.8″
  • 0.875″ diameter cross pin shaft applications only
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Yukon Gear – Bearing Race Driver (Part No.56020)

Bearing Race Driver

from

$215.99
Bearing race driver. No return.

Product Features:
  • Bearing race driver
  • Fits M802011 race
  • All steel construction
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Motive Gear – Differential Ring and Pinion (Part No.F9-471A)

Differential Ring and Pinion

from

$199.99
Motive Gear offers some of the toughest drive train components on the market today. If you are looking for the largest line of performance ring and pinion gear options available with gear sets in a wide range of ratios for nearly every application, both on and off-road, check out Motive Gear. Motive Gear products can be found in the winner’s circle at racing events worldwide. The superior quality of Motive Gear components is the result of years of racing development, outstanding design and state-of-the-art manufacturing methods. Extensive testing is performed on all products by our in-house engineers.
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National – Shaft Repair Sleeve (Part No.99199)

Shaft Repair Sleeve

from

$37.99
National has built a reputation as one of the most respected names in the industry. We have offered premium sealing solutions for more than 75 years. Our design team keeps pace with the industry and provides advanced solutions for today’s vehicles.

Product Features:
  • Designed to repair damaged, grooved or worn shafts
  • Durable stainless steel construction for corrosion-free sealing surface that surpasses most original shaft specifications
  • Ideal for a shaft where indications of seal wear, such as tracks or grooves have developed
  • Ultra-thin construction (0.01/0.25mm wall thickness) allows original seal size to be used with minimal additional lip loading
  • Easy to install with removable flange and installation tool
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Popular 1978 Mercury Grand Marquis Differentials Categories

Most Popular Differential Oil for 1978 Mercury Grand Marquis

Enhance your 1978 Mercury Grand Marquis with one of the 3 Differential Oil we have in stock, starting at just $99.99.

Yukon Gear – Redline Synthetic "Shock Proof" Oil With Positraction Additive – 4 Quarts (Part No.15005)

Redline Synthetic "Shock Proof" Oil With Positraction Additive - 4 Quarts

from

$148.99
Redline Synthetic “Shock Proof” Oil with positraction Additive. 4 Quarts.

Product Features:
  • Includes four quarts of Redline Shockproof oil and one 4oz bottle of Yukon positraction additive
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Yukon Gear – Redline Synthetic "Shock Proof" Oil – 3 Quarts (Part No.15000)

Redline Synthetic "Shock Proof" Oil - 3 Quarts

from

$99.99
Redline Synthetic “Shock Proof” Oil. 3 Quarts.

Product Features:
  • Includes three quarts of Redline Shockproof oil
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Yukon Gear – Redline Synthetic "Shock Proof" Oil – 4 Quarts (Part No.15004)

Redline Synthetic "Shock Proof" Oil - 4 Quarts

from

$137.99
Redline Synthetic “Shock Proof” Oil. 4 Quarts.

Product Features:
  • Includes four quarts of Redline Shockproof oil
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Best-Selling 1978 Mercury Grand Marquis Differential Pinion Seals

Upgrade your Grand Marquis with one of our 7 best-selling Differential Pinion Seals, earning an average 1 stars rating across 2 reviews.

Driveworks – Oil Seal (Part No.S-3604)

Oil Seal

from

$5.99
Value-priced seal meets all cataloged application requirements.

Product Features:
  • Brand may vary by location
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Driveworks – Oil Seal (Part No.S-7044NA)

Oil Seal

from

$6.49
Value-priced seal meets all cataloged application requirements.

Product Features:
  • Brand may vary by location
See More

Yukon Gear – Pinion Seal For ’61-’85 9" Ford (Part No.30137)

Pinion Seal For '61-'85 9" Ford

from

$17.99
Pinion seal for ’61-’85 9″ Ford. 3″ OD.Yukon Mighty seal.

Product Features:
  • Pinion seal
  • Fits 1961-1985 Ford 9″
  • 3.00″ O.D.
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FAG US – Shaft Seal (Part No.SS2934)

Shaft Seal

from

$21.79
Our wheel seals are engineered using only the highest-quality materials to meet vehicle manufacturer specificatons. We work with suppliers to design seals that meet FAG’s quality standards. Seals are designed to protect wheel end components from contamination – such as dirt, dust, and moisture – and prevent the loss of grease over the life of the bearing. The specifications for wheel seals are very demanding, and the type required depends on the specific application, position and vehicle class.

Product Features:
  • High-precision and High-quality components used in all KITs
  • Coverage of classic and new high-tech solutions for the best system coverage
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FAG US – Shaft Seal (Part No.SS2865)

Shaft Seal

from

$15.99
Our wheel seals are engineered using only the highest-quality materials to meet vehicle manufacturer specificatons. We work with suppliers to design seals that meet FAG’s quality standards. Seals are designed to protect wheel end components from contamination – such as dirt, dust, and moisture – and prevent the loss of grease over the life of the bearing. The specifications for wheel seals are very demanding, and the type required depends on the specific application, position and vehicle class.

Product Features:
  • High-precision and High-quality components used in all KITs
  • Coverage of classic and new high-tech solutions for the best system coverage
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Motive Gear – Differential Pinion Seal (Part No.7044NA)

Differential Pinion Seal

from

$12.99
All Motive Gear products are engineered for their specific application and manufactured in state of the art facilities. All of our products undergo rigid quality control processes to insure proper fit, performance and longevity. Motive Gear products can be found in the winners circle at NHRA, IHRA, NMRA, NMCA, SODA, SCORE, BITD, Ultra-4 and NASCAR events because we offer unmatched selection and quality demanded by racers and their crew chiefs – the same quality and selection demanded by DIY customers and top mechanics. With four warehouses strategically located across North America, most Motive Gear orders arrive within 2-4 days. Win with Motive Gear!
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Yukon Gear – Pinion Seal For 7.5", 8.8", And 9.75" Ford, And Also 1985-’86 9" Ford (Part No.30037)

Pinion Seal For 7.5", 8.8", And 9.75" Ford, And Also 1985-'86 9" Ford

from

$8.99
Pinion seal for 7.5″, 8.8″, and 9.75″ Ford, and also 1985-’86 9″ Ford.Yukon Mighty seal.

Product Features:
  • Pinion seal
  • Fits Ford 7.5″, 8.8″ and some 9.75″
  • 2.785″ O.D.
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Top-Quality Rear Differential Cover Gaskets for 1978 Mercury Grand Marquis

Choose a high-quality OEM or aftermarket Rear Differential Cover Gasket for Mercury Grand Marquis and enjoy top-notch performance from $11.99.

Yukon Gear – 9" Ford Gasket (Part No.23012)

9" Ford Gasket

from

$11.99
9″ Ford gasket.

Product Features:
  • Dropout gasket
  • Fits Ford 9″
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Yukon Gear – 8.8" Ford Cover Gasket (Part No.23011)

8.8" Ford Cover Gasket

from

$12.99
8.8″ Ford cover gasket.

Product Features:
  • Cover gasket
  • Fits Ford 8.8″
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Top Picks for 1978 Mercury Grand Marquis Differential Bearings

Invest in one of our 6 durable Differential Bearings for your 1978 Mercury, knowing you’re getting trusted brands and expert craftsmanship.

National – Bearing Race (Part No.LM102910)

Bearing Race

from

$7.79
Manufactured with premium-grade steel, National taper bearing cups feature crowned raceways to ensure even load distribution.

Product Features:
  • PREMIUM MATERIALS – Precision manufactured using premium-grade steel for outstanding durability and performance
  • SMOOTH ROTATION – Crowned raceways for even load distribution
  • OE-STYLE DESIGN – Engineered to meet OE specifications
  • COMPREHENSIVE COVERAGE – Industry-leading coverage for domestic and import applications
  • RIGOROUS TESTING – Comprehensive testing throughout design and development processes by National engineers for quality you can count on
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Yukon Gear – Pilot Bearing Retainer For Ford 9" (Part No.33255)

Pilot Bearing Retainer For Ford 9"

from

$11.99
Pilot bearing retainer for Ford 9″.

Product Features:
  • Pilot bearing retainer for Ford 9″
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FAG US – Bearing – TRB (Tapered Roller Bearing) (Part No.KT11)

Bearing - TRB (Tapered Roller Bearing)

from

$21.79
With advanced load-carrying capacity and compact design, tapered roller bearings are used in wheel bearings, transmissions, differentials, transfer cases and other miscellanous applications. FAG manufacturers over 100 million tapered roller bearings annually.

Product Features:
  • High-precision and High-quality components used in all KITs
  • Coverage of classic and new high-tech solutions for the best system coverage
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FAG US – Cup (Part No.M88010)

Cup

from

$11.29
With advanced load-carrying capacity and compact design, tapered roller bearings are used in wheel bearings, transmissions, differentials, transfer cases and other miscellanous applications. FAG manufacturers over 100 million tapered roller bearings annually.

Product Features:
  • High-precision and High-quality components used in all KITs
  • Coverage of classic and new high-tech solutions for the best system coverage
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National – Bearing Race (Part No.JL69310)

Bearing Race

from

$7.29
Product Features:
  • PREMIUM MATERIALS: Precision manufactured using premium-grade steel for outstanding durability and performance
  • SMOOTH ROTATION: Crowned raceways for even load distribution
  • OE-STYLE DESIGN: Engineered to meet OE specifications
  • COMPREHENSIVE COVERAGE: Industry-leading coverage for domestic and import applications
  • RIGOROUS TESTING: Comprehensive testing throughout design and development processes by National engineers for quality you can count on
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Yukon Gear – Cross Pin Bolt (Part No.33067)

Cross Pin Bolt

from

$6.99
Cross pin bolt for Chrysler 8.25″, 9.25″ rear, Ford 7.5″, 8.8″, GM 12 bolt car & truck, 7.2″ IFs, 7.5″, 7.6″, 8.0″, 8.25″ IFS & 8.5″.

Product Features:
  • Cross pin bolt for Chrysler 8.25″ and 9.25″ rear, Ford 7.5″ and 8.8″, GM 12 botl car and truck, 8.5″, 8.25″ IFS, 8.0″, 7.625″, 7.5″ and 7.2″ IFS
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Differential Covers for 1978 Mercury Grand Marquis

Make a smart move for your 1978 Mercury Grand Marquis with products all priced from $74.99 to $419.99.

Yukon Gear – Steel Cover For Ford 8.8" (Part No.32328)

Steel Cover For Ford 8.8"

from

$99.99
Yukon outer stub axle for Chrysler 9.25″ front. This axle uses a 1485 u/joint and has 33 splines.

Product Features:
  • Fits Ford 8.8″
  • Steel
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Yukon Gear – Chrome Cover For 8.8" Ford (Part No.32009)

Chrome Cover For 8.8" Ford

from

$74.99
Chrome cover for 8.8″ Ford.

Product Features:
  • Fits Ford 8.8″
  • Chrome
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Yukon Gear – 8.8" Ford Low Profile Ta HD Aluminum Rear Cover (Part No.32114)

8.8" Ford Low Profile Ta HD Aluminum Rear Cover

from

$419.99
8.8″ Ford low profile TA HD Aluminum rear Cover. This cover will not fit vehicles with independent rear suspension.

Product Features:
  • Fits Ford 8.8″
  • Aluminum girdle cover
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Top-Rated Differential Brands For Your 1978 Mercury Grand Marquis

When it comes to finding the perfect Differential for your 1978 Mercury Grand Marquis, Advance Auto Parts has you covered with a wide selection of high-quality OEM and aftermarket options from 11 trusted brands. We carry the most popular Differential brands including Powertrax, National, and Motive Gear, and more, all known for their exceptional customer ratings (average brand rating of 4.7 stars) and competitive prices, as low as $6.99. Purchasing a Differential from us here at Advance Auto Parts is a smart move for both you and your 1978 Mercury Grand Marquis, providing peace of mind with parts that meet or exceed OEM standards.

Popular Powertrax 1978 Mercury Grand Marquis Differentials

If you’re looking for a top-quality Differential for your 1978 Mercury Grand Marquis, Advance Auto Parts has exactly what you need with our selection of Powertrax Differentials. We have 1 Powertrax Differentials in stock for this fitment, all known for their durability and precision fit. With prices starting at just $551.99, you’ll find the perfect Differential for your needs and budget. Powertrax Differentials for the 1978 Mercury Grand Marquis come highly rated, with over 1 customer reviews and an impressive average rating of 4.7 stars. Choosing a Powertrax Differential from Advance Auto Parts is a smart move to ensure quality and value for your vehicle.
No-Slip Traction System
from $551.99
(1)
No-Slip Traction System
“Installed, no issues, works great.”

Top-Quality National 1978 Mercury Grand Marquis Differentials

For those in search of a high-quality Differential for their 1978 Mercury Grand Marquis, Advance Auto Parts offers a great selection of National Differentials. With 3 National Differentials in stock, you can trust you’re getting top-tier parts designed for durability and a perfect fit. Prices for these Differentials start at just $7.79, with an average price of $17.92, giving you a range of options to suit your budget. Backed by over 11 customer ratings and an average rating of 4.3 stars, National Differentials provide both reliability and excellent performance. Choosing a National Differential from Advance Auto Parts is a smart investment in your vehicle’s performance and longevity.
Bearing Race
from $7.99
(4)
Bearing Race
“Goes with M88010 bearing cup. Application was the pinion bearing race for a Ford 9 Inch on a 1957 Ford F-100.”
Bearing Race
from $7.79
(6)
Bearing Race
“perfect fit”
Shaft Repair Sleeve
from $37.99
(1)
Shaft Repair Sleeve
“Very delicate piece, but came shipped quite safely and not damaged. High quality.”

FAQs for 1978 Mercury Grand Marquis Differentials

What are the best-selling Differentials for 1978 Mercury Grand Marquis?

Out of 384 Differentials that fit 1978 Mercury Grand Marquis, the following parts are the top sellers:

What’s the price range for 1978 Mercury Grand Marquis Differentials?

The prices of Differentials for the 1978 Mercury Grand Marquis range from $1.99 up to $1,211.99 for the most premium parts.

What is the average price of a Differential for a 1978 Mercury Grand Marquis?

The average price for Differentials for the 1978 Mercury Grand Marquis is $263.37. Keep in mind the variety of part types within our Differential category, where you are likely to find a wide range of prices across a variety of parts and components.

Does Advance Auto Parts sell Differentials for other Mercury Grand Marquis model years?

Yes, we carry Differentials for 35 model years of Mercury Grand Marquis between 1975 and 2011. The following model years are the most popular for Differential purchases: 2011, 2010, 2009, 2008, 2007, 2006, 2005, 2004, and 2003.

What are the cheapest Differentials for my 1978 Mercury Grand Marquis?

The cheapest 1978 Mercury Grand Marquis Differentials we carry are:

Does Advance Auto Parts sell Differentials for any other 1978 Mercury models?

Yes. We stock Differentials for 4 other popular 1978 Mercury models. Some of the most popular are 1978 Cougar Differentials, 1978 Zephyr Differentials, 1978 Marquis Differentials, 1978 Monarch Differentials, and 1978 Bobcat Differentials.

What are the top-rated Differentials that fit the 1978 Mercury Grand Marquis?

The one 1978 Mercury Grand Marquis Differential we have in stock is the Ring Gear Bolt. It costs $1.99.

What types of Differentials do you sell for my 1978 Mercury Grand Marquis?

As of 11/2/25, these are some of the most in-demand types of Differentials for a 1978 Mercury Grand Marquis:

Can I get help with 1978 Mercury Grand Marquis Differential orders?

Contact our customer support team by chat or phone, through the help desk page, where you can find instant answers about Mercury Differentials and more.

What is your return policy for Mercury Grand Marquis Differentials?

Advance Auto Parts keeps returns simple. For new Mercury Grand Marquis Differentials and accessories, your online orders can be returned, in their original condition, within 45 days. For requirements, see the returns page.