1998 Mercury Mountaineer Differentials

Keep Your 1998 Mercury Mountaineer in Top Shape with Quality Differentials

Whether you’re repairing or upgrading your Differential, using high-quality parts is key to keeping your 1998 Mercury Mountaineer looking sharp and performing at its best. At Advance Auto Parts we carry a wide selection of dependable options, including Rear Differential Cover Gaskets, Differential Bearings, and Differential Oil. 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 Valvoline. For example, Motive Gear Differentials start at just $2.99 with an average 4.0 star rating. National and Valvoline offer similar pricing and quality, backed by strong customer feedback. With over 862 reviews and a solid 4 star average, you can shop with confidence knowing other Mercury Mountaineer owners approve.

Competitive Prices and Extensive Inventory

The average price for a 1998 Mercury Mountaineer Differential at Advance Auto Parts is around $212.02, with a range that starts at $1.29 and goes up to $1,539.99. With 215 options in stock from 19 trusted brands, finding the right fit is easy. Popular picks like DEX/MERC ATF Conventional Automatic Transmission Fluid, 1 Quart, Flex Fill Transmission & Differential Gear Oil: Full Synthetic 75W-90, 1 Quart, and Axle Housing Cover Gasket Rectangular Shaped, 10 Bolt Hole Gasket start at just $11.99 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 4WD Components and Universal Joints. At Advance Auto Parts, we’re here to help you keep your 1998 Mercury Mountaineer in peak condition, inside and out.

Looking for the perfect Differential for your 1998 Mercury Mountaineer? You’re in the right place. Below, you’ll find links to various types of Differentials that fit your vehicle. At Advance Auto Parts, we offer only the highest quality OEM and aftermarket Differentials, ensuring durability and a precise fit for your Mercury Mountaineer. Whether you’re driving a 1998 model or another popular model year like 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, and 2010, we’ve got you covered. Purchasing Differentials from Advance Auto Parts is a smart choice, giving you access to trusted brands and parts built to perform. Below, you’ll find links to various types of Differentials that fit your vehicle.

Essential 1998 Mercury Mountaineer Differentials

from

$7.99

Pinion nut for Ford 7.5″, 8″, 8.8″, 9 3/8″ & 9″. 1 1/6″ socket, 3/4″ x 20 thread.

Product Features:

Pinion nut for Ford 7.5″, 8″ and 9″
3/4″ x 20 thread
1 1/6″ socket

from

$258.99

Axle shaft damaged or bearings worn out? This axle shaft directly replaces the original equipment on certain vehicles, complete with all necessary application-specific installation components.

Product Features:

Direct replacement – this axle shaft replaces the original equipment on specific vehicle years, makes and models
Complete kit – each shaft includes critical installation hardware and components needed for specific vehicle applications
Durable construction – designed to rigorous standards and tested to ensure performance
Trustworthy solution – backed by team of engineers and quality control specialists in the United States

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$2.99

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

Product Features:

All products are designed to meet or exceed OE quality, form, fit and funtion.

from

$364.99

Yukon Ring & Pinion sets give you the confidence of knowing you’re running gears designed for the harshest of conditions. Whether it’s on the street, off-road, or at the track; Yukon ring & pinion sets deliver unrivaled performance & quality. Yukon uses the latest designs and manufacturing technologies to provide a quiet running gear that is strong and easy to set up. All Yukon ring & pinion sets come standard with a one-year warranty.

Product Features:

Fits standard rotation AMC Model 35
7.562″ ring gear diameter
26 spline pinion
8 ring gear bolts
4.88 ratio

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$17.49

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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$681.99

For vehicles that are driven daily, the Powertrax 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 Powertrax No-Slip locker easily installs in to your differential carrier using basic tools and without affecting your ring and pinion settings. Powertrax Grip-Lok, Lock-Right Lockers and No-Slip Traction Systems automatically provide 100% traction on-demand, under the toughest circumstances. The Powertrax Grip-Pro and Grip-LS performance limited slips offer smooth dependable torque transfer and traction for the best of both worlds!

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$12.99

8.8″ Ford cover gasket.

Product Features:

Cover gasket
Fits Ford 8.8″

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$7.99

High-quality Differential Component Shim

Product Features:

SHIM KIT FITS-8.25-F7.5-AMC20-GM0

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$249.99

Product Features:

Installation kit
Includes o-ring for bulkhead fitting, bulkhead fitting, outer fitting, switch, front and rear switch cover, solenoid, zip ties and 20′ air line

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$404.99

Product Features:

Clutch kit
Fits Ford 8.8″, 1963-1979 Corvette, GM 12 bolt passenger car and truck, 8.2″, 8.5″ and 8.6″ Dura Grip positraction
14 piece kit
Carbon fiber clutches

from

$16.99

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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$194.99

Mini Spool for Ford 8.8″ with 31 spline axles and 7/8″ cross pin. Mini spools are a low-cost traction option for vehicles looking for full-time lockup. The mini spool installs into a standard open carrier and give 100% power to both tires at all times. These units are not recommended for street-driven vehicles. We recommend full spools for vehicles with large tires or high horsepower. These units come with a one year warranty against manufacturing defects.

Product Features:

Fits Ford 8.8″ with 31 spline axles
Provides 100% traction to both wheels at all times
Installs into standard open carrier case

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$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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$109.99

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 & SEAL FORD 8.8″

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$299.99

Product Features:

Spider gear kit
Fits Ford 8.8″ 31 spline Trac Loc positraction
Includes two side gears, two pinion gears, cross pin shaft, cross pin bolt and spider gear thrust washers.

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$98.99

Yukon Carrier installation kits are great, low cost kit for carrier changes such as Positraction or locker upgrades. Carrier installation kit for AMC Model 35 differential. This kit contains carrier bearings, races and shims.

Product Features:

Fits AMC Model 35 with 27 spline axles
Includes carrier bearings and races and “super” carrier shim kit

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$164.99

Yukon replacement standard open carrier case for Dana 30, 3.73 & up, 1.943″ tall. If purchasing this case for a D30 JK front, you will need to also purchase spider gear set YPKD30-S-27.

Product Features:

Standard open carrier case
Fits Dana Spicer 30
3.73 and up ratio only
Does not include spider gears

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$53.99

The FAG repair sleeve is a precision element that provides additional sealing for damaged shafts. Made of heat-treated stainless steel, the FAG repair sleeve signifcantly increases the life of the shaft and prevents premature wear. Since no shaft removal or machining is required during the repair, the repair sleeve is a cost effective repair solution to protect damaged surfaces.

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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$15.49

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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$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

from

$19.99

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

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$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

from

$99.99

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

Product Features:

All products are designed to meet or exceed OE quality, form, fit and funtion.

from

$883.99

The Yukon carrier bearing Puller works with an impact gun to quickly and safely remove carrier bearings without damaging them. This unit comes with a handy bench top stand and works with up to one ton applications including Dana 70HD, Dana 80, 10.25″ & 10.5″ Ford, or GM & Chrysler 11.5″ differentials.

Product Features:

Carrier bearing puller
Works with an impact gun to safely and easliy remove carrrier bearings

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$5.99

Ford 7.5″ & 8.8″ ring gear bolt, standard Open & TracLoc. 7/16″ x 20.

Product Features:

Ring gear bolt for Ford 7.5″ and 8.8″
7/16″ x 20

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$41.99

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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$35.99

Product Features:

MINI INSTALL KIT FORD 8.8

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$215.99

Bearing race driver. No return.

Product Features:

Bearing race driver
Fits M802011 race
All steel construction

Popular 1998 Mercury Mountaineer Differentials Categories

Differential Oil

Differential Pinion Yokes

Pinion Shaft Bearings

Rear Differential Cover Gaskets

Differential Open Unit and Components

Differential Covers

Differential Pinion Shaft Lock Bolts

Differential Bearings

Differential Axle Shafts

Differential Pinion Pilot Bearings

Differential Cover Bolts

Differential Carriers

Differential Bearing Kits

Front Differential Pinion Bearings

Differential Spider Gear Kits

Differential Rebuild Kits

Differential Carrier Shim Kits

Differential Pinion Seals

Differential Disc Kits

Differential Clutch Packs

Differential Ring and Pinions

Differential End Yokes

Differential Lock Assemblies

Rear Differential Pinion Bearings

Differential Spools

Differential Carrier Bearings

Differential Lock Springs

Differential Pinion Bearing Kits

Complete Differentials

Differential Ring Gear Bolts

Bearing Race Drivers

Differential Carrier Bearing Shims

Differential Crush Sleeves

Differential Side Bearing Spacers

Differential Pinion Shims

Differential Pinion Shaft Nuts

Differential Gear Install Kits

Differential Cross Pins

Differential Side Gear Thrust Washers

Differential Pinion Bearing Baffles

Differential Pinion Gear Thrust Washers

Differential Drive Pinion Oil Deflectors

Auxiliary Shaft Bearings

Limited Slip Differential Assemblies

Differential Spider and Pinion Gear Kits

Most Popular Rear Differential Cover Gaskets for 1998 Mercury Mountaineers

Enhance your 1998 Mercury Mountaineer with one of the 3 Rear Differential Cover Gaskets we have in stock, starting at just $4.99.

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$15.99

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

from

$12.99

8.8″ Ford cover gasket.

Product Features:

Cover gasket
Fits Ford 8.8″

from

$4.99

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

Product Features:

All products are designed to meet or exceed OE quality, form, fit and funtion.

Best-Selling 1998 Mercury Mountaineer Differential Bearings

Upgrade your Mountaineer with one of our 6 best-selling Differential Bearings, earning an average 4 stars rating across 5 reviews.

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from

$9.29

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

from

$27.99

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

from

$19.99

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

from

$21.29

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

from

$11.29

High-precision and High-quality components used in all KITs
Coverage of classic and new high-tech solutions for the best system coverage

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

Top-Quality Differential Oil for 1998 Mercury Mountaineers

Choose a high-quality OEM or aftermarket Differential Oil for Mercury Mountaineers and enjoy top-notch performance from $10.29.

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from

$14.49

Valvoline DEXRON-VI/MERCON LV ATF is a full-synthetic transmission fluid formulated with advanced additive technology to meet and exceed the requirements of the General Motors DEXRON-VI specification. It is officially licensed and approved by GM and is fully back-serviceable and can be used wherever DEXRON-II and/or DEXRON-III are recommended. Recommended for use in the following applications: DEXRON-VI, DEXRON-III, DEXRON-II, and Allison C-4.

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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$69.99

Valvoline SAE 75W-140 Full Synthetic Gear Oil provides the ultimate gear protection in hypoid rear differentials and non-synchronized manual transmissions. Engineered to outperform, our formulation provides exceptional high and low temperature protection and excellent thermal stability, especially in demanding driving situations such as towing and off-roading. It contains an extreme pressure additive for better load carrying capacity and wear resistance, a limited slip additive for optimal clutch pack performance, and an anti-foaming agent for better lubrication and service life. It’s recommended for conventional rear axles and transmissions requiring EP gear lubes under high speed, high load, high torque and high horsepower conditions.

Product Features:

EXCEPTIONAL HIGH AND LOW TEMPERATURE PROTECTION ranging from -22F to 390F degrees
REDUCES CHATTERING AND PROTECTS GEAR TEETH from oxidation, rust, and wear
FIGHTS CORROSION AND RUST with emulsifying agents and safeguards against impurities, oxidation and thermal breakdown
MEETS THE DEMANDS OF CONVENTIONAL AND LIMITED SLIP REAR DIFFERENTIALS where API GL-5 is specified, as well as non-synchronized manual transmissions that require API GL-4
MEETS OR EXCEEDS PERFORMANCE REQUIREMENTS for Ford M2C-192A, GM 12346140, Chrysler MS-8985 and API GL-5

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$11.99

Valvoline DEX/MERC ATF is a high-quality transmission fluid formulated to meet the challenging demands of many automatic transmissions. Its responsive low-temperature fluidity is beneficial in both electronic and hydraulic controlled transmissions and transaxles. Recommended for use in the following applications: MERCON*, DEXRON*-III, Ford M2C138-CJ and M2C166-H, Allison C-4 and TES-389, and Caterpillar TO-2.

Product Features:

Formulated with premium 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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$18.99

We’ve squeezed innovation into every ounce of Valvoline FlexFill SAE 75W-90 Full Synthetic Gear Oil, the ultimate gear protection in hypoid rear differentials and non-synchronized manual transmissions. Our unique new flexible pouch makes getting into the tightest places to lubricate gears easier than ever and with less waste. The superior detergent package-based formulation contains fully synthetic basestocks and special additives that help protect parts from rust and corrosion while providing exceptional high and low temperature protection and excellent thermal stability, especially in demanding driving situations such as towing and off-roading. It contains an extreme pressure additive for better load carrying capacity, wear resistance additives that assist in protecting gear teeth, a limited slip additive for optimal clutch pack performance, and an anti-foaming agent for better lubrication and service life. Valvoline FlexFill SAE 75W-90 Full Synthetic Gear Oil is recommended for use in axle applications requiring factory-fill or drain-and-fill levels for limited slip performance.

Product Features:

FLEXIBLE POUCH FOR EASIER USE WITH LESS WASTE in tight, hard to reach undercarriage situations.
EXCEPTIONAL HIGH AND LOW TEMPERATURE PROTECTION ranging from -30F to 300F degrees for dependable coverage year-round
REDUCES CHATTERING AND PROTECTS GEAR TEETH from oxidation, rust, and wear
MEETS THE DEMANDS OF CONVENTIONAL AND LIMITED SLIP REAR DIFFERENTIALS where API GL-5 is specified, as well as non-synchronized manual transmissions that require API GL-4 or MT-1 fluid
MEETS OR EXCEEDS PERFORMANCE REQUIREMENTS for Mack GO-H and GO-J; API GL-5 and API MT-1; MIL-PRF-2105E; and SAE J2360

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$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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$99.99

Redline Synthetic “Shock Proof” Oil. 3 Quarts.

Product Features:

Includes three quarts of Redline Shockproof oil

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$137.99

Redline Synthetic “Shock Proof” Oil. 4 Quarts.

Product Features:

Includes four quarts of Redline Shockproof oil

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$10.29

Formulated to meet the specific requirements of Subaru vehicles equipped with conventional (non-CVT) transmissions up to model year 2005. Recommended for service-fill in all Subaru automatic transmissions where SUBARU ATF HP is specified. Fuel economy demands and more sophisticated electronic controls have made automatic transmissions not only more complex, but also unique to each vehicle manufacturer. Long gone are the days of having just a couple choices of automatic transmission fluid type. Idemitsu is the factory fill Automatic Transmission Fluid (ATF) supplier to most Asian imports. Idemitsu application-specific ATF products match the exact friction materials and performance requirements of each different vehicle model for which they are made.

Product Features:

Excellent resistance to oxidation and thermal breakdown provide long fluid life and extended protection
Precisely engineered frictional characteristics guarantee smooth shifting and outstanding anti-shudder performance
Excellent resistance to oxidation and thermal breakdown provide long fluid life and extended protection
Excellent seal compatibility and conditioning reduces risk of fluid leaks due to seal shrinkage, hardening and cracking
Advanced anti-wear technology provides maximum protection to gears and bearings
Precisely engineered frictional characteristics guarantee smooth shifting and outstanding anti-shudder performance
Provides superior cleanliness, maintaining the transmission free of sludge and varnish deposits
Excellent seal compatibility and conditioning reduces risk of fluid leaks due to seal shrinkage, hardening and cracking
Advanced anti-wear technology provides maximum protection to gears and bearings

Top Picks for 1998 Mercury Mountaineer Differential Covers

Invest in one of our 6 durable Differential Covers for your 1998 Mercury, knowing you’re getting trusted brands and expert craftsmanship.

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from

$41.99

This direct replacement differential cover matches the fit and function of the original equipment diff cover for a reliable, leak-free repair. It features a durable design, made to strict specifications, to help ensure reliable service life.

Product Features:

Direct replacement – this differential cover matches the fit and function of the original equipment diff cover on select vehicles
Reliable repair – the smart solution for fixing an existing cover that’s rusted, damaged or leaking differential fluid
Durable construction – this differential cover is made according to strict engineering standards to help ensure dependability
Trustworthy quality – backed by a team of product experts in the United States and more than a century of automotive experience

from

$37.99

DIFF COVER KIT

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

from

$74.99

Chrome cover for 8.8″ Ford.

Product Features:

Fits Ford 8.8″
Chrome

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

from

$269.99

B&M Cast Aluminum Differential Covers are designed to strengthen the differential by preventing case distortion and ring gear & bearing cap deflection. Constructed of A356.0-T6 aluminum, these rugged covers significantly increase the fluid capacity and dissipate heat much faster than the stock factory unit to prolong the life of your ring and pinion gears. Additional features include an engraved B&M logo, drain and fill port locations, a magnetic drain plug for catching ferrous metal particles, and complete hardware and installation instructions.

Product Features:

Additional Oil Capacity
More Cooling Ability
No Dipstick Modification
Some Include Fluid Pickup Extension
Built-In Drain Plugs
Cast Aluminum

Top-Rated Differential Pinion Seals for 1998 Mercury Mountaineers

Make a smart move for your 1998 Mercury Mountaineer with products all priced from $5.99 to $23.79.

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from

$5.99

Value-priced seal meets all cataloged application requirements.

Product Features:

Brand may vary by location

from

$10.99

Value-priced seal meets all cataloged application requirements.

Product Features:

Brand may vary by location

from

$23.79

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

from

$15.99

High-precision and High-quality components used in all KITs
Coverage of classic and new high-tech solutions for the best system coverage

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.

Top-Rated Differential Brands For Your 1998 Mercury Mountaineer

When it comes to finding the perfect Differential for your 1998 Mercury Mountaineer, Advance Auto Parts has you covered with a wide selection of high-quality OEM and aftermarket options from 19 trusted brands. We carry the most popular Differential brands including Valvoline, 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 $2.99. Purchasing a Differential from us here at Advance Auto Parts is a smart move for both you and your 1998 Mercury Mountaineer, providing peace of mind with parts that meet or exceed OEM standards.

Popular Valvoline 1998 Mercury Mountaineer Differentials

If you’re looking for a top-quality Differential for your 1998 Mercury Mountaineer, Advance Auto Parts has exactly what you need with our selection of Valvoline Differentials. We have 2 Valvoline Differentials in stock for this fitment, all known for their durability and precision fit. With prices starting at just $14.49 and an average cost of $42.24, you’ll find the perfect Differential for your needs and budget. Valvoline Differentials for the 1998 Mercury Mountaineer come highly rated, with over 366 customer reviews and an impressive average rating of 4.8 stars. Choosing a Valvoline Differential from Advance Auto Parts is a smart move to ensure quality and value for your vehicle.

from $69.99

(364)

SynPower Transmission & Differential Gear Oil: Full Synthetic 75W-140, 1 Gallon

“Happy with purchase”

from $14.49

(2)

DEXRON – VI ATF Full Synthetic Automatic Transmission Fluid, 1 Quart

“I’ve used this in my 2005 2500HD since I bought the truck with 20k on it now at 280k changed every other year maybe 40k I’d put on in two years, I pu”

Top-Quality National 1998 Mercury Mountaineer Differentials

For those in search of a high-quality Differential for their 1998 Mercury Mountaineer, 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 $7.99, with an average price of $11.42, giving you a range of options to suit your budget. Backed by over 45 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.

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.”

from $16.99

(39)

Multi-Purpose Bearing

“Great bearings”

from $9.29

(2)

Bearing Race

“Reasonable price and woks well. front diff 2006 Escalade esv”

FAQs for 1998 Mercury Mountaineer Differentials

What are the best-selling Differentials for 1998 Mercury Mountaineers?

Out of 215 Differentials that fit 1998 Mercury Mountaineers, the following parts are the top sellers:

DEX/MERC ATF Conventional Automatic Transmission Fluid, 1 Quart (12079139) – $11.99
Flex Fill Transmission & Differential Gear Oil: Full Synthetic 75W-90, 1 Quart (12507273) – $18.99
Axle Housing Cover Gasket Rectangular Shaped, 10 Bolt Hole Gasket (5782406) – $15.99

What’s the price range for 1998 Mercury Mountaineer Differentials?

The prices of Differentials for the 1998 Mercury Mountaineer range from $1.29 up to $1,539.99 for the most premium parts.

What is the average price of a Differential for a 1998 Mercury Mountaineer?

The average price for Differentials for the 1998 Mercury Mountaineer is $212.02. 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 Mountaineer model years?

Yes, we carry Differentials for 12 model years of Mercury Mountaineers between 1997 and 2010. The following model years are the most popular for Differential purchases: 2010, 2009, 2008, 2007, 2006, 2005, 2004, 2003, and 2002.

What are the cheapest Differentials for my 1998 Mercury Mountaineer?

The cheapest 1998 Mercury Mountaineer Differentials we carry are:

Differential Ring Gear Bolt (10282257) – $1.29
Ring Gear Bolt (20520509) – $1.99
Differential Ring Gear Bolt (10282436) – $1.99
Differential Crush Sleeve (20520219) – $2.99
Differential Cross Shaft (10282201) – $2.99

Does Advance Auto Parts sell Differentials for any other 1998 Mercury models?

Yes. We stock Differentials for 4 other popular 1998 Mercury models. Some of the most popular are 1998 Grand Marquis Differentials, 1998 Tracer Differentials, 1998 Mystique Differentials, 1998 Villager Differentials, and 1998 Sable Differentials.

What are the top-rated Differentials that fit the 1998 Mercury Mountaineer?

The one 1998 Mercury Mountaineer Differential we have in stock is the Differential Ring Gear Bolt. It costs $1.29.

What types of Differentials do you sell for my 1998 Mercury Mountaineer?

As of 11/2/25, these are some of the most in-demand types of Differentials for a 1998 Mercury Mountaineer:

Can I get help with 1998 Mercury Mountaineer 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 Mountaineer Differentials?

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

1998 Mercury Mountaineer Differentials

Yukon Gear – Pinion Nut (Part No.33154)

Dorman – Axle Shaft (Part No.630-229)

Pro-King – Differential Cross Shaft (Part No.742G930)

Yukon Gear – High Performance Ring & Pinion Gear Set For Model 35 In A 4.88 Ratio (Part No.24183)

Motive Gear – Differential Pinion Seal (Part No.470331N)

Powertrax – Grip LOK Traction System (Part No.LK443527)

Yukon Gear – 8.8" Ford Cover Gasket (Part No.23011)

Motive Gear – Differential Pinion Shim Kit (Part No.1100)

Yukon Gear – Zip Locker Install Kit (Part No.34026)

Yukon Gear – 14 Plate Carbon Clutches For GM 8.2", GM 8.5", 12T, 12P, Ford 8.8" & Cast Iron ‘Vette (Part No.16041)

National – Multi-Purpose Bearing (Part No.A-5)

Yukon Gear – Mini Spool For Ford 8.8" With 31 Spline Axles (Part No.32226)

Yukon Gear – Super Carrier Shim Kit For Ford 8.8", GM 12 Bolt Car & Truck, 8.6 & Vette (Part No.55002)

Motive Gear – Differential Bearing Kit – Timken (Part No.R8.8RT)

USA Standard Gear – Standard Spider Gear Set For Ford 8.8" Trac Loc Posi, 31 Spline (Part No.39032)

Yukon Gear – Carrier Installation Kit For Amc Model 35 Differential (Part No.57011)

Yukon Gear – Replacement Standard Open Carrier Case For Dana 30, 3.73 & Up (Part No.20026)

FAG US – Repair Sleeve (Part No.SR3506)

National – Bearing Race (Part No.HM88610)

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

National – Tapered Roller Bearing Cone (Part No.LM501349)

Dorman – Differential Clutch Kit (Part No.697-780)

Pro-King – Differential Internal Nest Kit (Part No.762B717A)

Yukon Gear – The Carrier Bearing Puller (Part No.56072)

Yukon Gear – Ford 7.5" & 8.8" Ring Gear Bolt, Standard Open & Tracloc (Part No.33053)

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

Motive Gear – Differential Gear Install Kit (Part No.F8.8IK)

Yukon Gear – Bearing Race Driver (Part No.56020)

Felpro – Axle Housing Cover Gasket Rectangular Shaped, 10 Bolt Hole Gasket (Part No.RDS 55341)

Yukon Gear – 8.8" Ford Cover Gasket (Part No.23011)

Pro-King – Differential Cover Gasket (Part No.762B303)

National – Bearing Race (Part No.LM501314)

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

National – Tapered Roller Bearing Cone (Part No.LM501349)

FAG US – Bearing – TRB (Tapered Roller Bearing) (Part No.KT5)

FAG US – Cup (Part No.M88010)

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

Valvoline – DEXRON – VI ATF Full Synthetic Automatic Transmission Fluid, 1 Quart (Part No.822405)

Valvoline – SynPower Transmission & Differential Gear Oil: Full Synthetic 75W-140, 1 Gallon (Part No.887344)

Valvoline – DEX/MERC ATF Conventional Automatic Transmission Fluid, 1 Quart (Part No.798153)

Valvoline – Flex Fill Transmission & Differential Gear Oil: Full Synthetic 75W-90, 1 Quart (Part No.889785)

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

Yukon Gear – Redline Synthetic "Shock Proof" Oil – 3 Quarts (Part No.15000)

Yukon Gear – Redline Synthetic "Shock Proof" Oil – 4 Quarts (Part No.15004)

Idemitsu – Type HP Automatic Transmission Fluid , 1 Quart (Part No.10107-042F)

Dorman – Differential Cover (Part No.697-702)

ATP – DIFF COVER KIT (Part No.111103)

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

Yukon Gear – Chrome Cover For 8.8" Ford (Part No.32009)

Yukon Gear – 8.8" Ford Low Profile Ta HD Aluminum Rear Cover (Part No.32114)

B & M – Rear End Cover 1 EA B&M (Part No.40297)

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

Driveworks – Oil Seal (Part No.S-714675)

FAG US – Shaft Seal (Part No.SS2876)

FAG US – Shaft Seal (Part No.SS2865)

Yukon Gear – Pinion Seal For 7.5", 8.8", And 9.75" Ford, And Also 1985-’86 9" Ford (Part No.30037)