1990 Mercury Cougar Differentials

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Keep Your 1990 Mercury Cougar in Top Shape with Quality Differentials

Whether you’re repairing or upgrading your Differential, using high-quality parts is key to keeping your 1990 Mercury Cougar looking sharp and performing at its best. At Advance Auto Parts we carry a wide selection of dependable options, including Differential Bearings, Rear Housing Cover Gaskets, and Differential Covers. 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 Motive Gear, National, and Royal Purple. For example, Motive Gear Differentials start at just $7.99 with an average 4.0 star rating. National and Royal Purple offer similar pricing and quality, backed by strong customer feedback. With over 823 reviews and a solid 4 star average, you can shop with confidence knowing other Mercury Cougar owners approve.

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 1990 Mercury Cougar in peak condition, inside and out.

Essential 1990 Mercury Cougar Differentials

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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Royal Purple – MaxGear SAE 75W90 High Performance Gear Oil w/Friction Modifier Additive, 1 QT (Part No.01300)

MaxGear SAE 75W90 High Performance Gear Oil w/Friction Modifier Additive, 1 QT

from

$24.99
Max Gear is recommended for truck and automotive differentials, outboard motor lower units or in rear axles or manual transmissions requiring an API fluid. Max Gear is a high performance automotive gear oil designed to provide maximum protection to heavily loaded gears while increasing power throughput through the drive train. Max Gear virtually eliminates both gear and bearing wear-even under severe squeeze film conditions caused by extremely high loads, sudden shock loads or low RPMs. Slippery, synthetic molecules not only reduce wear and friction but significantly increase Max Gear’s cold weather fluidity and lubricity, making it the ideal choice for vehicles operating in cold climates. Gears run smoother, quieter, cooler and longer without overhauls. It is noncorrosive to both ferrous and nonferrous metals.

Product Features:
  • Maximizes horsepower
  • Extends gear and bearing life
  • Reduces operating temperature
  • Lower coefficient of friction
  • Superior corrosion protection
  • Separates rapidly from water
  • For use with open, limited-slip and locking differential
  • Contains limited-slip friction modifier
  • Made in USA
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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
Yukon Gear & Axle manufactures a full line of top quality small parts to complete any job including ring gear bolts, crush sleeves, pinion nuts and washers, axle studs, thrust washers and much, much more. For all your differential small parts needs, look no further than Yukon.

Product Features:
  • Side gear thrust washer for Ford 8.8″
  • 0.875″ diameter cross pin shaft applications only
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Yukon Gear – Pinion Gear and Thrust Washer for 8" and 9" Ford, Model 20, and 7.25" Chrysler (Part No.33301)

Pinion Gear and Thrust Washer for 8" and 9" Ford, Model 20, and 7.25" Chrysler

from

$4.99
Yukon Gear & Axle manufactures a full line of top quality small parts to complete any job including ring gear bolts, crush sleeves, pinion nuts and washers, axle studs, thrust washers and much, much more. For all your differential small parts needs, look no further than Yukon.

Product Features:
  • Pinion gear thrust washer for Ford 8″, Ford 9″ and Chrysler 7.25″
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National – Multi-Purpose Bearing (Part No.R-1535-TAV)

Multi-Purpose Bearing

from

$41.99
Manufactured with premium-grade steel, National cylindrical outer races are designed and engineered to meet OE specifications.

Product Features:
  • PREMIUM MATERIALS: Precision manufactured using premium-grade steel for outstanding durability and performance
  • STRONG AND DURABLE: Controlled heat treatment process for strength and durability
  • 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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Motive Gear – Differential Gear Install Kit (Part No.F7.5IK)

Differential Gear Install Kit

from

$35.49


Product Features:
  • MINI INSTALL KIT FORD 7.5
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Yukon Gear – 8.5" & 8.2" GM carrier installation kit (Part No.57008)

8.5" & 8.2" GM carrier installation kit

from

$109.99
Yukon Carrier Installation Kits are a convenient and low-cost solution for carrier changes in cases where one is upgrading to a positraction limited slip differential, a mechanical locker, or an air operated locker. These kits contain carrier bearings and races and a carrier shim kit.

Product Features:
  • Fits GM 7.5″, 7.625″ 8.2″ and 8.5″
  • Includes carrier bearings and races and “super” carrier shim kit
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Motive Gear – Differential Ring and Pinion (Part No.F8.8-327)

Differential Ring and Pinion

from

$235.99


Product Features:
  • FRD 10BL 8.8 R/P 3.27 MG
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Richmond Gear – Differential Mini Spool (Part No.78-8831-1)

Differential Mini Spool

from

$151.99
Richmond Gear is the leading manufacturer of professional quality, high-performance drivetrain products. Our complete line of products ranges from high performance ring-and-pinion sets for serious street and racing applications to torque-hungry manual transmissions and components. Richmond Gear products have been winners both at the Daytona 500 and U.S. Nationals for decades. WINNERS RUN RICHMOND.
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USA Standard Gear – Pinion Installation Kit For ’09 & Down Ford 8.8 (Part No.60009)

Pinion Installation Kit For '09 & Down Ford 8.8

from

$119.99
8.8″ FORD 09 & DWN PINION KIT .

Product Features:
  • Fits 2009 and down Ford 8.8″
  • Uses Koyo bearings and races
  • Included are pinion bearings and races, pinion seal, pinion nut, crush sleeve, marking compound and brush.
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Yukon Gear – Grizzly Locker For Ford 9" With 31 Spline Axles, Fits Load Bolt Housing (Part No.28033)

Grizzly Locker For Ford 9" With 31 Spline Axles, Fits Load Bolt Housing

from

$993.99
The Yukon Grizzly Locker is the ultimate in locking differentials for street, off-road, & drag racing. Grizzly Lockers provide 100% power to both tires, while still allowing for disengagement while negotiating turns. The Yukon Grizzly locker uses 8620 internals and a patented design to provide maximum strength and reduce common failures. Assembled in the USA! This unit has been approved for competition in NASCAR National & Touring series. All Grizzly Lockers are backed by the best warranty in the business! Yukon covers the replacement unit and covers any collaterally damaged parts and associated labor, up to $2,000! This locker also fits 9.5″ & 10″ dropouts.

Product Features:
  • Fits Ford 9″ with 31 spline axles and loadbolt housing
  • Patented internal design reduces common locker failures
  • 8620 internals for added strength
  • Assembled in the USA
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Felpro – Axle Housing Cover Gasket Round Shaped 10 Bolt Hole Gasket (Part No.RDS 55459)

Axle Housing Cover Gasket Round 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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LuK – Repair Kit, Differential (Part No.GDK313)

Repair Kit, Differential

from

$291.99
Each LuK Differential Bearing Kit contains all the OE quality bearings needed for a professional transmission repair. Differential bearing kits are the perfect repair solution for a broken transmission. We carefully select OE quality components for each individual transmission for a professional repair.

Product Features:
  • LuK Differential Bearing Kits are designed to meet or exceed OEM requirements. This will ensure customer satisfaction.
  • LuK Differential Bearing Kits contain the bearings and seals needed to complete the job.
  • LuK Differential Bearing Kits include wear parts such as seals, O-rings, shaft sealing rings, support bearings and spare parts where necessary for eliminating the specific cause of failure.
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USA Standard Gear – Differential Open Unit/Component (Part No.59023)

Differential Open Unit/Component

from

$57.99
USA Standard 30 spline 4340 Chrome-Moly axle & Zip Locker kit for Jeep TJ, XJ, YJ & ZJ. This kit contains a 4340 Chrome-Moly axle kit, Grizzly locker (fits 3.73 & up), disconnect block-off kit & two Yukon Super Joints.

Product Features:
  • Fits Ford 9″ with 31 spline axles
  • Installs into a standard open carrier case
  • Provides 100% traction to both wheels at all times
  • Not recommended for street driven vehicles
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Pro-King – Differential Crush Sleeve (Part No.761A034)

Differential Crush Sleeve

from

$2.99
Pro-King is the leading supplier of transmission and driveline products in the aftermarket.

Product Features:
  • Meets or exceeds OE specifications
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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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Richmond Gear – Differential Pinion Shaft (Part No.CSPF88L)

Differential Pinion Shaft

from

$26.99
Richmond Gear is the leading manufacturer of professional quality, high-performance drivetrain products. Our complete line of products ranges from high performance ring-and-pinion sets for serious street and racing applications to torque-hungry manual transmissions and components. Richmond Gear products have been winners both at the Daytona 500 and U.S. Nationals for decades. WINNERS RUN RICHMOND.

Product Features:
  • For over 80-years, the Richmond Double-Diamond logo has represented some of the highest quality gears in the racing industry. Winners Run Richmond.
  • The superior quality of Richmond gearsets is a result of outstanding design, world class manufacturing and an extensive testing process that is performed on all products.
  • Richmond performance gearsets have been winners for decades at: NHRA, NMRA, NMCA, Daytona 500, WISSOTA and U.S. Nationals.
  • Richmond Gear is a leading manufacturer of high performance ring and pinion gearsets and drivetrain components, backed by limited warranty.
  • Engineered to perform faster and be more reliable, Richmond performance drivetrain products are the result of a continuous research and development program combined with state-of-the-art manufacturing capabilities.
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Motive Gear – Differential Pinion Bearing Spacer (Part No.SS9)

Differential Pinion Bearing Spacer

from

$45.99
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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Yukon Gear – Chrome Moly Cross Pin Shaft for Mini-Spool for 9" Ford (Part No.32235)

Chrome Moly Cross Pin Shaft for Mini-Spool for 9" Ford

from

$61.99
Yukon Gear & Axle manufactures a full line of top quality small parts to complete any job including ring gear bolts, crush sleeves, pinion nuts and washers, axle studs, thrust washers and much, much more. For all your differential small parts needs, look no further than Yukon.

Product Features:
  • Cross pin shaft
  • Fits Ford 9″
  • Chromoly steel for added strength
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Pro-King – Differential Cross Shaft (Part No.742G930)

Differential Cross Shaft

from

$2.99
Pro-King is the leading supplier of transmission and driveline products in the aftermarket.

Product Features:
  • Meets or exceeds OE specifications
See More

Yukon Gear – Spider Gear Kit for Ford 8.8", 31 Spline, Trac Loc Posi (Part No.16106)

Spider Gear Kit for Ford 8.8", 31 Spline, Trac Loc Posi

from

$363.99
Yukon Gear & Axle spider gear kits feature higher quality materials and better manufacturing techniques than OEM to ensure a longer lasting spider gear set. Kit delivers everything needed for a complete and proper spider gear set replacement.

Product Features:
  • Spider gear kit
  • Fit Ford 8.8″ Trac Loc positraction with 31 spline axles
  • Includes two side gears, two pinion gears, cross pin shaft, cross pin bolt and spider gear thrust washers.
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Powertrax – Differential Lock Assembly (Part No.9206883108)

Differential Lock Assembly

from

$544.99
For vehicles that are driven daily, the Power Trax No-Slip Traction System is the latest design in quiet traction-adding differential technology. It combines the automatic street-friendly smooth operation of a limited-slip differential with the traction performance of a locking differential. The Power Trax No-Slip locker easily installs in to your differential carrier using basic tools and without affecting your ring and pinion settings. Power Trax Grip-Lok, Lock-Right Lockers and No-Slip Traction Systems automatically provide 100% traction on-demand, under the toughest circumstances. The Power Trax Grip-Pro and Grip-LS performance limited slips offer smooth dependable torque transfer and traction for the best of both worlds.

Product Features:
  • The Power Trax Lock-Right Locker provides outstanding traction for off-road machines and race vehicles. Power Trax No-Slip Traction Systems deliver excellent performance to street-driven cars and trucks.
  • Power Trax lockers range from the original, Lock-Right for serious straight-line performance, to the No-Slip traction system for street-able vehicles.
  • Power Trax offers three levels of GRIP locking differentials, ranging from the clutch-type GRIP LS with a forged steel case, the gear-driven GRIP PRO and finally the GRIP LOK for extreme traction.
  • Power Trax ia an Extreme Traction System
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Yukon Gear – Pinion Depth Shims for Ford 8" (Part No.55055)

Pinion Depth Shims for Ford 8"

from

$31.99
Yukon shim kits are precision machined and tailored for each individual application to ensure you have the right shims for every set up.

Product Features:
  • Pinion depth shims for Ford 8″
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Dorman – Differential Pinion Yoke Assembly (Part No.697-539)

Differential Pinion Yoke Assembly

from

$125.99
Worn or damaged differential end yoke causing driveline Vibrations- This direct replacement end yoke matches the original equipment part for a trustworthy repair and reliable performance.

Product Features:
  • Direct replacement – this differential end yoke matches the fit and construction of the original yoke
  • Excellent value – this replacement end yoke offers original equipment quality at a fraction of the price of dealer parts
  • Quality materials – this end yoke is machined from cast iron for strength and is precision machined for reliability
  • Validated fit – this differential end yoke has been tested to confirm accurate fit
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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
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Yukon Gear – 8.8" Ford Tracloc Clutch Set, Both Sides (Part No.16017)

8.8" Ford Tracloc Clutch Set, Both Sides

from

$207.99
Yukon Gear & Axle clutch kits fit popular Ford diffs outfitted with a Trac Loc style positraction unit feature stout clutch plates, ensuring total traction and long-lasting performance.

Product Features:
  • Clutch kit
  • Fit Ford 8.8″ Trac Loc positraction
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Mr. Gasket – Rear End Gasket – Ford 9" – Blend Of Nitrile Rubber And Fiber For Excellent Sealing And Durability (Part No.82)

Rear End Gasket - Ford 9" - Blend Of Nitrile Rubber And Fiber For Excellent Sealing And Durability

from

$25.99
Mr. Gasket Axle Housing/Differential Cover or Rear End Gaskets are manufactured from a .047 inch thick cellulose/nitrile composite gasket material for excellent sealing and durability. They are precision die-cut for an excellent fit. Fits 1957-1981 Ford 10 bolt 9 inch ring gear.

Product Features:
  • .047″ thick cellulose/nitrile composite gasket material
  • Precision die cut
  • Reusable
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Yukon Gear – One (1) Specialty Bearing Race To Adapt Small Bearing Journal Into 3.25" Dropout (Part No.32157)

One (1) Specialty Bearing Race To Adapt Small Bearing Journal Into 3.25" Dropout

from

$51.99
Yukon Gear & Axle manufactures a full line of top-quality small parts to complete any job including ring gear bolts, crush sleeves, pinion nuts and washers, axle studs, thrust washers, and other general maintenance items. For all your differential small parts needs, look no further than Yukon.

Product Features:
  • Carrier race
  • Fits Ford 9″
  • Conversion race to install small bearing carrier into 3.250″ dropout
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Most Popular Differential Bearings for 1990 Mercury Cougars

Enhance your 1990 Mercury Cougar with one of the 6 Differential Bearings we have in stock, starting at just $6.99.

National – Bearing Race (Part No.LM501314)

Bearing Race

from

$11.99
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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National – Multi-Purpose Bearing (Part No.A-36)

Multi-Purpose Bearing

from

$27.99
Manufactured with premium-grade steel, National taper bearing sets feature crowned raceways and rollers to ensure even load distribution.

Product Features:
  • CONSISTENT PERFORMANCE: Matched cup and cone components ensure consistent performance
  • PREMIUM MATERIALS: Precision manufactured using premium-grade steel for outstanding durability and performance
  • SMOOTH ROTATION: Crowned raceways and rollers 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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National – Tapered Roller Bearing Cone (Part No.LM501349)

Tapered Roller Bearing Cone

from

$21.99
Manufactured with premium-grade steel, National taper bearing cones feature crowned raceways and rollers to ensure even load distribution.

Product Features:
  • PREMIUM MATERIALS – Precision manufactured using premium-grade steel for outstanding durability and performance
  • SMOOTH ROTATION – Crowned raceways and rollers 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
See More

Schaeffler – Bearing – TRB (Tapered Roller Bearing) (Part No.KT5)

Bearing - TRB (Tapered Roller Bearing)

from

$14.99
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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Schaeffler – Cup (Part No.M88010)

Cup

from

$10.99
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
See More

Yukon Gear – Cross Pin Bolt (Part No.33067)

Cross Pin Bolt

from

$6.99
Yukon Gear & Axle manufactures a full line of top quality small parts to complete any job including ring gear bolts, crush sleeves, pinion nuts and washers, axle studs, thrust washers and much, much more. For all your differential small parts needs, look no further than Yukon.

Product Features:
  • Cross pin bolt for Chrysler 8.25″ and 9.25″ rear, Ford 7.5″ and 8.8″, GM 12 bolt car and truck, 8.5″, 8.25″ IFS, 8.0″, 7.625″, 7.5″ and 7.2″ IFS
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Best-Selling 1990 Mercury Cougar Rear Housing Cover Gasket

Upgrade your Cougar with our best-selling Rear Housing Cover Gasket.

Felpro – Axle Housing Cover Gasket Round Shaped 10 Bolt Hole Gasket (Part No.RDS 55459)

Axle Housing Cover Gasket Round 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
See More

Top-Quality Differential Covers for 1990 Mercury Cougars

Choose a high-quality OEM or aftermarket Differential Cover for Mercury Cougars and enjoy top-notch performance from $99.99.

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

Steel Cover for Ford 8.8"

from

$99.99
These Yukon replacement diff covers are a direct bolt-on.

Product Features:
  • Fits Ford 8.8″
  • Steel
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Yukon Gear – Ford OEM Steel Differential Cover (Part No.32364)

Ford OEM Steel Differential Cover

from

$99.99
These Yukon replacement diff covers are a direct bolt-on.
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Top Picks for 1990 Mercury Cougar Rear Differential Cover Gaskets

Invest in one of our 4 durable Rear Differential Cover Gaskets for your 1990 Mercury, knowing you’re getting trusted brands and expert craftsmanship.

Felpro – Axle Housing Cover Gasket Round Shaped 10 Bolt Hole Gasket (Part No.RDS 55460)

Axle Housing Cover Gasket Round Shaped 10 Bolt Hole Gasket

from

$8.99
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
  • Engineered for the sealing repair environment
  • Validated for fit, form and function
  • Unsurpassed quality you can trust
See More

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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Spicer – Performance Differential Gasket – Ford 8.8 Axle (Part No.RD52005)

Performance Differential Gasket - Ford 8.8 Axle

from

$26.99
Spicer performance differential cover gaskets offer all-makes coverage for street, strip, drag, and off-road applications. These gaskets are reusable offering a clean release during replacement. Built with a mechanically and chemically bonder woven steel.

Product Features:
  • Made to adhere without messy RTV sealant This saves on install time by eliminating the time needed for RTV cure.
  • Provides no re-torque design with maximum compression and sealing.
  • Manufactured with proprietary high-density performance material.
  • Made in the USA.
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Pro-King – Differential Cover Gasket (Part No.762B303)

Differential Cover Gasket

from

$4.99
Pro-King is the leading supplier of transmission and driveline products in the aftermarket.

Product Features:
  • Meets or exceeds OE specifications
See More

Top-Rated Differential Oil for 1990 Mercury Cougars

Make a smart move for your 1990 Mercury Cougar with products all priced from $12.49 to $148.99.

Royal Purple – High Performance 5W-30 Synthetic Engine Oil, Better Wear Protection, 5 Quart (Part No.51530)

High Performance 5W-30 Synthetic Engine Oil, Better Wear Protection, 5 Quart

from

$45.99
Royal Purple Motor Oil is a specially formulated multi viscocity oil for use in gasoline and diesel engines of all types from cars and trucks to SUVs, motorcycles and boats. Royal Purple(R) Motor Oil with Synerlec(R) additive technology reduces friction, which results in a 1-3 percent increase in horsepower, lowers operating temperatures, provides superior corrosion protection, improves fuel economy, reduces emissions and extends oil life. A.P.I. Certified.

Product Features:
  • Better wear protection
  • Increased fuel efficiency
  • Better protection of the expensive catalytic emission system
  • Improved compatibility with fuels containing ethanol
  • Superior corrosion protection
  • Meets ILSAC GF-5 and Dexos1 performance requirements
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Valvoline – MaxLife Multi-Vehicle (ATF) Full Synthetic Automatic Transmission Fluid, 1 Quart (Part No.VV324)

MaxLife Multi-Vehicle (ATF) Full Synthetic Automatic Transmission Fluid, 1 Quart

from

$12.49
Valvoline Full Synthetic MaxLife Multi-Vehicle ATF, the No. 1 ATF product, suitable for use in 95% of vehicles. And now, it’s recommended for most belt & chain-driven continuously variable transmissions (CVT). Featuring advanced additives to prevent the major causes of transmission breakdown, it’s designed to help prevent leaks, reduce wear & tear, and maximize performance. Has improved thermal stability for longer fluid life, better viscosity stability for consistent transmission operation, and frictional enhancements for smooth gear engagements. Valv MaxLife Multi-Vehicle ATF is suitable for most Ford, GM, Toyota, Honda, Nissan, Hyundai, Subaru, BMW, Mercedes, Volvo, VW & Audi vehicles. Recommended for use in: GM DEXRON-II, DEXRON-III, DEXRON-VI, and DEX-CVT; Ford MERCON LV; Toyota/Lexus Type T, T-II, T-IV, WS, CVTF FE, and CVTF TC; Honda/Acura ATF-Z1 and Honda CVT; Nissan/Infiniti Matic-D, Matic-J, Matic-K and Matic-S; Hyundai/Kia SP-II, SP-III, SP-IV and SPH-IV; BMW 7045E, ETL 8072B, LA2634 and LT71141; Allison C-4; Mercedes-Benz NAG-1; Volvo 1161521, 1161540, 97340 and 1273.41; Subaru ATF HP, Lineartronic chain CVT and CVT-II, Lineartronic High Torque CVT, and CV-30; and VW/Audi G-052-025-A2 and G-052-162-A1. CURRENTLY UNABLE TO SHIP THIS PRODUCT TO CUSTOMERS LOCATED IN CALIFORNIA

Product Features:
  • FOR USE IN 95% OF VEHICLES INCLUDING MOST CVTs in operation with US registered light duty applications
  • HIGH PERFORMANCE CONDITIONING AGENTS prolong seal elasticity to prevent leaks
  • IMPROVED DURABILITY & TRANSMISSION LIFE with anti-wear technology to avoid costly repairs
  • ENHANCED HIGH & LOW TEMP PERFORMANCE supports transmission fluid in all weather situations
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Royal Purple – High Performance 5W-30 Synthetic Motor Oil, Better Wear Protection, 1 Quart (Part No.01530)

High Performance 5W-30 Synthetic Motor Oil, Better Wear Protection, 1 Quart

from

$12.99
High Performance Motor Oil API LICENSED MOTOR OIL Royal Purple High Performance Motor Oil combines premium base oils with proprietary additive technologies to create a high performance synthetic engine oil that optimizes performance and protection. Royal Purple High Performance Motor Oils carry the current API and ILSAC engine oil licenses, as well as the GM dexos1 gasoline engine oil approval. ILSAC GF-6 AND GM DEXOS1 Modern gasoline direct injection (GDI) engines have achieved levels of power and fuel economy never before possible in passenger car engines. As a result, smaller engines operate at much higher loads across all engine speeds. This has caused increased wear in critical areas of the engine, and created a destructive phenomenon called low-speed pre-ignition (LSPI). The unique, state-of-the-art additive technology in Royal Purple High Performance engine oils is designed specifically to address these issues, and help engines maintain performance and reliability.

Product Features:
  • Better Wear Protection
  • Increased Protection against Low Speed Pre-Ignition
  • Increased Fuel Efficiency
  • Better Protection for Vehicle Exhaust Emissions Equipment
  • Improved Compatibility with Fuels Containing Ethanol
  • Superior Corrosion Protection
  • Made in USA
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Valvoline – Import Multi-Vehicle Synthetic Automatic Transmission Fluid, 1 Quart (Part No.822389)

Import Multi-Vehicle Synthetic Automatic Transmission Fluid, 1 Quart

from

$14.99
Valvoline Import Multi-Vehicle Automatic Transmission Fluid is specifically formulated for use in most Toyota, Nissan, Honda and other imported vehicles. It is formulated with all synthetic base stocks and a proprietary additive system to ensure optimal transmission performance in a wide variety of vehicles. Valvoline Import Multi-Vehicle ATF can also be used in many domestic vehicles. It meets requirements of General Motors and Ford vehicles. Recommended for use in the following applications: Ford MERCON, GM DEXRON-II and DEXRON-III, BMW LT 71141 and ETL-7045E, Nissan/Infiniti Nissan ATF, Matic-D, Matic-K and Matic-J, Mitsubishi Diamond SP-II and SP-III, Subaru ATF-HP, Hyundai/ KIA SP-II and SP-III, Toyota/Lexus Type T, T-III and T-IV, Honda/Acura ATF-Z1 (except in CVTs), Mercedes Benz NAG1, Volvo passenger car (except AW-1), and Volkswagen/Audi TL52162. For CVT applications Valvoline recommends Valvoline Full Synthetic CVT Fluid.

Product Features:
  • Formulated with full-synthetic base stocks and advanced additive technology to meet the challenging demands of automatic transmissions
  • Enhanced anti-shudder protection for smooth shifting and maximum power transfer
  • Developed with anti-wear technology to help improve transmission durability
  • Engineered with a proprietary blend of base oils and advanced additives to provide better oil flow at low temperatures and greater film protection at higher temperatures
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Yukon Gear – 3 Qt – 80W90 Conventional Gear Oil with Posi Additive (Part No.15003)

3 Qt - 80W90 Conventional Gear Oil with Posi Additive

from

$57.99
Union 76 gear oil is a conventional non-synthetic 80W90 formulation designed for all types of differentials. This kit includes three quarts of oil and a bottle of Yukon Limited Slip Friction modifier that reduces noise and chatter in clutch driven positraction units and limited slip differentials.

Product Features:
  • Includes three quarts of conventional oil and one 4oz bottle of Yukon positraction additive
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Yukon Gear – 3 Qt – Penzoil 80W90 Conventional Gear Oil (Part No.15002)

3 Qt - Penzoil 80W90 Conventional Gear Oil

from

$44.99
Union 76 gear oil is a conventional non-synthetic 80W90 formulation designed for all types of differentials.

Product Features:
  • Includes three quarts of conventional oil
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Royal Purple – HMX 5W-30 High Mileage Synthetic Motor Oil, Restores Engine Performance, 5 Quart (Part No.11748)

HMX 5W-30 High Mileage Synthetic Motor Oil, Restores Engine Performance, 5 Quart

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$66.99
Royal Purple HMX SAE 5W-30 High-Mileage Synthetic Motor Oil, 5 quart is specifically designed to minimize wear and restore lost performance in engines with more than 75,000 miles. Formulated with robust zinc/phosphorus anti-wear compounds combined with Royal Purple’s proprietary additive technology Synerlec, HMX is chemically enhanced to revitalize hardened seals, reducing oil consumption common in high-mileage engines. In addition, HMX is fortified with stout detergents to remove engine build-up and deposits, maintain cleanliness and promote engine longevity. 

Product Features:
  • Specifically designed to minimize wear and restore lost performance in engines with more than 75,000 miles
  • Formulated with robust zinc/phosphorus anti-wear compounds combined with Royal Purple’s proprietary additive technology
  • HMX is chemically enhanced to revitalize hardened seals, reducing oil consumption common in high-mileage engines
  • Reduces friction and metal-to-metal contact for peak engine performance
  • Also provides outstanding oxidation resistance to safely extend oil drain intervals, and an ionic attraction to metal surfaces, providing protection and minimizing wear at start-up
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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 Heavy Shockproof Gear Oil is formulated to provide lasting protection. This kit includes four quarts of oil and a bottle of Yukon Limited Slip Friction modifier that reduces noise and chatter in clutch driven positraction units and limited slip differentials.

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 Heavy Shockproof Gear Oil is formulated to provide lasting protection.

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 Heavy Shockproof Gear Oil is formulated to provide lasting protection.

Product Features:
  • Includes four quarts of Redline Shockproof oil
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Top-Rated Differential Brands For Your 1990 Mercury Cougar

When it comes to finding the perfect Differential for your 1990 Mercury Cougar, Advance Auto Parts has you covered with a wide selection of high-quality OEM and aftermarket options from 16 trusted brands. We carry the most popular Differential brands including Royal Purple, National, and Motive Gear, and more, all known for their exceptional customer ratings (average brand rating of 4.8 stars) and competitive prices, as low as $7.99. Purchasing a Differential from us here at Advance Auto Parts is a smart move for both you and your 1990 Mercury Cougar, providing peace of mind with parts that meet or exceed OEM standards.

Popular Royal Purple 1990 Mercury Cougar Differentials

If you’re looking for a top-quality Differential for your 1990 Mercury Cougar, Advance Auto Parts has exactly what you need with our selection of Royal Purple Differentials. We have 2 Royal Purple Differentials in stock for this fitment, all known for their durability and precision fit. With prices starting at just $12.99 and an average cost of $29.49, you’ll find the perfect Differential for your needs and budget. Royal Purple Differentials for the 1990 Mercury Cougar come highly rated, with over 215 customer reviews and an impressive average rating of 4.8 stars. Choosing a Royal Purple Differential from Advance Auto Parts is a smart move to ensure quality and value for your vehicle.

Top-Quality National 1990 Mercury Cougar Differentials

For those in search of a high-quality Differential for their 1990 Mercury Cougar, 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 $11.99, with an average price of $22.42, giving you a range of options to suit your budget. Backed by over 31 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.
Shaft Repair Sleeve
from $41.99
(1)
Shaft Repair Sleeve
“Very delicate piece, but came shipped quite safely and not damaged. High quality.”
Multi-Purpose Seal
from $13.29
(28)
Multi-Purpose Seal
“05 F150, 4.6L 4×4, 8.8 Rear End, Pinion Seal This was a high quality seal. It is easy to tap in because on the metal ring on the outside of the seal. ”
Bearing Race
from $11.99
(2)
Bearing Race
“Reasonable price and woks well. front diff 2006 Escalade esv”

FAQs for 1990 Mercury Cougar Differentials

What are the best-selling Differentials for 1990 Mercury Cougars?

Out of 154 Differentials that fit 1990 Mercury Cougars, the following parts are the top sellers:

What’s the price range for 1990 Mercury Cougar Differentials?

The prices of Differentials for the 1990 Mercury Cougar range from $1.29 up to $1,115.99 for the most premium parts.

What is the average price of a Differential for a 1990 Mercury Cougar?

The average price for Differentials for the 1990 Mercury Cougar is $185.33. 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 Cougar model years?

Yes, we carry Differentials for 33 model years of Mercury Cougars between 1967 and 2002. The following model years are the most popular for Differential purchases: 2002, 2001, 2000, 1999, 1997, 1996, 1995, 1994, and 1993.

What are the cheapest Differentials for my 1990 Mercury Cougar?

The cheapest 1990 Mercury Cougar Differentials we carry are:

Does Advance Auto Parts sell Differentials for any other 1990 Mercury models?

Yes. We stock Differentials for 3 other popular 1990 Mercury models. Some of the most popular are 1990 Grand Marquis Differentials, 1990 Colony Park Differentials, 1990 Topaz Differentials, and 1990 Sable Differentials.

What types of Differentials do you sell for my 1990 Mercury Cougar?

As of 6/2/26, these are some of the most in-demand types of Differentials for a 1990 Mercury Cougar:

Can I get help with 1990 Mercury Cougar 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 Cougar Differentials?

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