1999 Mercury Mountaineer Differentials

Please Select your Vehicle to See Exact Fit Parts

Keep Your 1999 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 1999 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 Covers, and Rear Housing 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 Motive Gear, National, and Valvoline. For example, Motive Gear Differentials start at just $2.79 with an average 4.0 star rating. National and Valvoline offer similar pricing and quality, backed by strong customer feedback. With over 1,638 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 1999 Mercury Mountaineer Differential at Advance Auto Parts is around $200.51, with a range that starts at $1.29 and goes up to $1,481.99. With 211 options in stock from 21 trusted brands, finding the right fit is easy. Popular picks like Mobil 1 Synthetic Gear Lubricant LS 75W-140, 1 Quart, Axle Housing Cover Gasket Rectangular Shaped, 10 Bolt Hole Gasket, and Multi-Purpose Seal start at just $13.29 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 1999 Mercury Mountaineer in peak condition, inside and out.

Essential 1999 Mercury Mountaineer Differentials

Dorman – Differential Pinion Yoke Assembly (Part No.697-532)

Differential Pinion Yoke Assembly

from

$194.99
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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Yukon Gear – Dana 30 Side Gear Thrust Washer (Part No.33284)

Dana 30 Side Gear Thrust Washer

from

$10.99
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 Dana Spicer 25, 27, 30 and AMC Model 35
  • 1.560″ I.D.
  • Fits standard open differentials only
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Yukon Gear – Trac Loc Spring for Ford 8.8", 28 Spline (Part No.33515)

Trac Loc Spring for Ford 8.8", 28 Spline

from

$63.99
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:
  • Trac Loc spring
  • Fits 28 spline Ford 8.8
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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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Driveworks – Taper Bearing Cup (Part No.S-LM-501314)

Taper Bearing Cup

from

$7.99
Value-priced bearing meets all cataloged application requirements.

Product Features:
  • Brand may vary by location
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Powertrax – Differential Lock Assembly (Part No.1822-LR)

Differential Lock Assembly

from

$371.99
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 – Dana 25, 27, 30, 44, Model 20 And Model 35, GM 7.5", 8.2", 8.5", 12P, 12T, C9.25 Rear Cover Bolt (Part No.33286)

Dana 25, 27, 30, 44, Model 20 And Model 35, GM 7.5", 8.2", 8.5", 12P, 12T, C9.25 Rear Cover Bolt

from

$9.99
5/16″-18 cover bolt, Dana Spicer 25, 27, 30 and 44, AMC Model 20 and Model 35, Chrysler 9.25 rear, GM 7.5″, 7.625″, 8.2″, 8.5″, 12 bolt passenger car and truck.

Product Features:
  • Cover bolt for Dana Spicer 25, 27, 30 and 44, AMC Model 20 and Model 35, GM 7.5″, 7.625″, 8.2″, 8.5″ and 12 bolt passenger car and truck.
  • 1/2″ head
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National – Axle Differential Bearing & Seal Kit (Part No.RA-311MK)

Axle Differential Bearing & Seal Kit

from

$116.99
The National bearing & seal kit includes all the components required to complete the repair.

Product Features:
  • COMPLETE SOLUTION – Includes everything needed to complete the repair
  • STRONG AND DURABLE – Controlled heat treatment process for strength and durability
  • 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
  • Professional technicians know they can depend on National
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Yukon Gear – Dura Grip Positraction For Ford 8.8" With 31 Spline Axles (Part No.26006)

Dura Grip Positraction For Ford 8.8" With 31 Spline Axles

from

$857.99
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 Dura Grip uses a nodular case and forged 4320 internals for added strength along with composite clutches for high performance and long life. All units are Rebuildable and many offer upgrades to increase aggressiveness for racing applications. Each unit carries a one year warranty against defects.

Product Features:
  • Fits Ford 8.8″ with 31 spline axles
  • 4-spring, clutch style positraction
  • Internal gears are manufactured using forged 4320 steel and cut to provide stronger teeth
  • Fully rebuildable
  • Assembled in the USA
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Yukon Gear – Replacement Ring Gear Bolt For Model 20, Grand Cherokee 35, "Super" Dana 30 & Dana 50 – 7/16" X 20 (Part No.33040)

Replacement Ring Gear Bolt For Model 20, Grand Cherokee 35, "Super" Dana 30 & Dana 50 - 7/16" X 20

from

$3.99
Replacement ring gear bolt for Model 20, Grand Cherokee 35, “Super” Dana 30 & Dana 50. 7/16″ x 20.

Product Features:
  • Ring gear bolt for AMC Model 20, “Super” 35, Dana Spicer “Super” 30 and Dana Spicer 50
  • 7/16″ 20 thread
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Yukon Gear – Pinion Nut, M20/35, D30/44 JK front, Ford 10.25"/10.5"/some 9.75" 7/8-20 Thread (Part No.33146)

Pinion Nut, M20/35, D30/44 JK front, Ford 10.25"/10.5"/some 9.75" 7/8-20 Thread

from

$10.99
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 nut for Jeep JK front, Jeep Liberty front, Ford 9.75″, 10.25″, 10.5″ and AMC Model 20 and Model 35
  • 7/8″ x 20 thread
  • 1 1/8″ socket
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Yukon Gear – Pinion Gear and Thrust Washer (0.875" Shaft) for 8.8" Ford (Part No.33299)

Pinion 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:
  • Pinion gear thrust washer for Ford 8.8″
  • 0.875″ diameter cross pin shaft applications only
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Motive Gear – Differential Gear Install Kit (Part No.F8.8IK)

Differential Gear Install Kit

from

$35.99


Product Features:
  • MINI INSTALL KIT FORD 8.8
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National – Shaft Repair Sleeve (Part No.99166)

Shaft Repair Sleeve

from

$34.99
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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Dorman – Differential Cover (Part No.697-702)

Differential Cover

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
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Pro-King – Differential Internal Nest Kit (Part No.762B717)

Differential Internal Nest Kit

from

$239.99
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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Yukon Gear – 14 Plate Carbon Clutches, GM 8.2"/GM 8.5"/12T/12P/Ford 8.8"/Cast Iron Vette (Part No.16041)

14 Plate Carbon Clutches, GM 8.2"/GM 8.5"/12T/12P/Ford 8.8"/Cast Iron Vette

from

$404.99
Yukon Gear & Axle clutch kits fit popular GM diffs outfitted with a Yukon Dura Grip positraction unit feature 14 advanced carbon clutch plates, ensuring total traction and long-lasting performance.

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
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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
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:
  • 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 Shim Kit (Part No.1100)

Differential Pinion Shim Kit

from

$7.99
High-quality Differential Component Shim

Product Features:
  • SHIM KIT FITS-8.25-F7.5-AMC20-GM0
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Yukon Gear – Trac Loc Positraction, Ford 8.8", 31 Spline (Part No.20069)

Trac Loc Positraction, Ford 8.8", 31 Spline

from

$719.99
Main Cap stud kit for Ford 7.5″, 8.8″, 9″, 10.25″, Dana 44, 60, and 70.

Product Features:
  • Trac Loc positraction
  • Fits Ford 8.8″ with 31 spline axles
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Schaeffler – Shaft Seal (Part No.SS2865)

Shaft Seal

from

$11.99
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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Yukon Gear – 8.8" Ford 7/8" Diameter Notched Cross Pin shaft (.875" for ’86 and Newer) (Part No.33434)

8.8" Ford 7/8" Diameter Notched Cross Pin shaft (.875" for '86 and Newer)

from

$57.99
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:
  • Notched cross pin shaft for Ford 8.8″
  • 0.875″ diameter
  • Not compatible with Spartan Locker or Powertrax Lock Right
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Motive Gear – Differential Ring and Pinion (Part No.F8.8-355A)

Differential Ring and Pinion

from

$179.99


Product Features:
  • FRD 10BL 8.8 R/P 3.55A MG
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Yukon Gear – Standard Open Carrier Case, Ford 8.8", 31 Spline (Part No.20077)

Standard Open Carrier Case, Ford 8.8", 31 Spline

from

$269.99
8.8″ 31 spline standard Open case (7/8 X-PIN HOLE).

Product Features:
  • Standard open carrier case
  • Fits Ford 8.8″ with 31 spline axles
  • Does not include spider gears
  • 0.875″ cross pin shaft diameter
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Yukon Gear – Dana 30 / 44 Roll Pin replacement (Part No.33312)

Dana 30 / 44 Roll Pin replacement

from

$12.99
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:
  • Roll pin for Dana Spicer 30 and Dana Spicer 44
  • 0.235″ diameter
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Yukon Gear – Replacement Outer Oil Slinger For Dana 25, 27, 30, 44 & 50 (Part No.33011)

Replacement Outer Oil Slinger For Dana 25, 27, 30, 44 & 50

from

$5.99
Cut to length axle shaft for GM 10.5″ 14 bolt truck. This axle shaft covers lengths from 34.8″ to 38.8″. Yukon 1541H alloy axles offer a strength increase over stock while retaining a low cost. Yukon 1541H alloy rear axles come with a one year warranty against manufacturing defects. This is a 38 spline upgraded shaft. The factory spindles will need to be machined in order to accept these axles. Please verify bolt pattern on 2011 & later models. This axle has a 3.562″ bolt pattern. Some late model applcaitons use a larger bolt pattern.

Product Features:
  • Outer oil slinger for Dana Spicer 25, 27, 30, 44 and 50
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Sealed Power – Engine Auxiliary Shaft Bearing Set (Part No.1881M)

Engine Auxiliary Shaft Bearing Set

from

$36.99
Sealed Power parts provide innovative designs, use leading-edge materials and utilize ISO & QS certified manufacturing in order to deliver top quality products that meet the rigorous demands of today’s modern engines.

Product Features:
  • Steel-backed Babbitt lining material
  • Used in automotive and high-performance
  • Babbitt is designed to perform under extreme loads without damaging other engine parts
  • Babbitt is more environmentally friendly than other material
  • ISO & QS certified manufacturing
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Most Popular Rear Differential Cover Gaskets for 1999 Mercury Mountaineers

Enhance your 1999 Mercury Mountaineer with one of the 3 Rear Differential Cover Gaskets we have in stock, starting at just $4.99.

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

Best-Selling 1999 Mercury Mountaineer Differential Covers

Upgrade your Mountaineer with one of our 5 best-selling Differential Covers, earning an average 2.75 stars rating across 35 reviews.

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

Differential Cover

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
See More

ATP – Differential Cover Kit With Internal Magnet (Part No.111103)

Differential Cover Kit With Internal Magnet

from

$37.99
Differential covers can become damaged from road debris, corrosion, or bolt/drain plug over tightening. Their job is to act as a lid keeping lubricants in place for the ring and pinion gears, bearings, and bushings. Without lubricants, the differential quickly become damaged. ATP Differential Cover Kits include a replacement gasket and are designed to fit and function just like the original part ensuring long life and durability.
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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 – Chrome Cover for 8.8" Ford (Part No.32009)

Chrome Cover for 8.8" Ford

from

$74.99
These Yukon replacement diff covers take your rig a step beyond the boring factory look. They are the stock OE design finished in chrome.

Product Features:
  • Fits Ford 8.8″
  • Chrome
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B & M – Rear End Cover 1 EA B&M (Part No.40297)

Rear End Cover 1 EA B&M

from

$299.99
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
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Top-Quality Rear Housing Cover Gaskets for 1999 Mercury Mountaineers

Choose a high-quality OEM or aftermarket Rear Housing Cover Gasket for Mercury Mountaineers and enjoy top-notch performance from $15.99.

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

Axle Housing Cover Gasket Rectangular Shaped, 10 Bolt Hole Gasket

from

$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
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Top Picks for 1999 Mercury Mountaineer Differential Oil

Invest in one of our 10 durable Differential Oil for your 1999 Mercury, knowing you’re getting trusted brands and expert craftsmanship.

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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Mobil 1 – Mobil 1 Synthetic Gear Lubricant LS 75W-140, 1 Quart (Part No.44815)

Mobil 1 Synthetic Gear Lubricant LS 75W-140, 1 Quart

from

$21.99
Mobil 1 Synthetic Gear Lubricant LS 75W-140 is a supreme, multi-purpose automotive gear lubricant that helps to provide exceptional thermal stability and resistance to high temperature oxidation, extending gear life due to minimal deposits. Helps to deliver outstanding protection against low speed/high torque wear with the capability to handle severe driving conditions while delivering smooth efficient performance. Mobil 1 Synthetic Gear Lubricant LS provides exceptional shear stability, corrosion protection, and enhanced frictional properties. Compared to conventional hypoid gear lubricants, Mobil 1 LS 75W-140 performs exceptionally over a wide range of temperatures to reduce wear at start up. Mobil 1 gear lube helps to minimize leakage and reduce contamination, while providing a good resistance to foaming to maintain film strength for reliable lubrication. Meets or exceeds the requirements of the following industry specifications: API GL-5.

Product Features:
  • Mobil 1 synthetic automotive gear lubricant exceeds the highest level of performance requirements for modern passenger vehicles
  • Helps to provide exceptional thermal stability and resistance to high temperature oxidation and extend gear life due to minimal deposits
  • Delivers outstanding protection against low speed/high torque wear, handling severe driving conditions with smooth, efficient performance
  • Compared to conventional hypoid gear lubricants, performs exceptionally over a wide range of temperatures to reduce wear at start up
  • Provides exceptional shear stability, corrosion protection, and enhanced frictional properties
  • Manufacturer Part Number: 102490
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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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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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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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Valvoline – High Performance Transmission & Differential Gear Oil: Conventional 75W-90, 1 Quart (Part No.VV820)

High Performance Transmission & Differential Gear Oil: Conventional 75W-90, 1 Quart

from

$12.99
Valvoline High Performance Synthetic Gear Oil is the thermally stabile extreme pressure lubricant that offers outstanding protection for gearboxes and differentials in passenger cars, light trucks, and sport utility vehicles. Combined with high quality synthetic base oils, our formula’s superior additives help reliably safeguard against severe temperatures, shock loads, foaming, scuffing, scouring, corrosion and pitting in high load, high torque and high horsepower conditions. Can be used in conventional and limited slip hypoid differentials where GL-5 is specified as well as non-synchronized manual transmissions that require GL-4. Protect your gears with Valvoline, the #1 gear oil brand.

Product Features:
  • HIGH PERFORMANCE EXTREME-PRESSURE ADDITIVES HELP MINIMIZE WEAR in high pressure and high temperature conditions
  • EXCEPTIONAL HIGH AND LOW TEMPERATURE PROTECTION can easily handle both winter and summer conditions for dependable coverage and protection year-round
  • 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
  • SUPERIOR ADDITIVES help reliably safeguard against severe temperatures, shock loads, foaming, scuffing, scouring, corrosion and pitting in high load, high torque and high horsepower conditions
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Top-Rated Differential Bearings for 1999 Mercury Mountaineers

Make a smart move for your 1999 Mercury Mountaineer with products all priced from $6.99 to $27.99.

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
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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
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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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Schaeffler – Cup (Part No.LM48510)

Cup

from

$6.99
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

Top-Rated Differential Brands For Your 1999 Mercury Mountaineer

When it comes to finding the perfect Differential for your 1999 Mercury Mountaineer, Advance Auto Parts has you covered with a wide selection of high-quality OEM and aftermarket options from 21 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 $2.79. Purchasing a Differential from us here at Advance Auto Parts is a smart move for both you and your 1999 Mercury Mountaineer, providing peace of mind with parts that meet or exceed OEM standards.

Popular Valvoline 1999 Mercury Mountaineer Differentials

If you’re looking for a top-quality Differential for your 1999 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 $12.49 and an average cost of $13.74, you’ll find the perfect Differential for your needs and budget. Valvoline Differentials for the 1999 Mercury Mountaineer come highly rated, with over 454 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.
Import Multi-Vehicle Synthetic Automatic Transmission Fluid, 1 Quart
from $14.99
(8)
Import Multi-Vehicle Synthetic Automatic Transmission Fluid, 1 Quart
“My 1999 Honda Accord 4-cylinder has over 250K miles and a drain and fill takes exactly 3 quarts of Import ATF. I do this with every oil change. No pro”

Top-Quality National 1999 Mercury Mountaineer Differentials

For those in search of a high-quality Differential for their 1999 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 $11.99, with an average price of $17.09, giving you a range of options to suit your budget. Backed by over 37 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.
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”
Tapered Roller Bearing Cone
from $25.99
(7)
Tapered Roller Bearing Cone
“Good price”

FAQs for 1999 Mercury Mountaineer Differentials

What are the best-selling Differentials for 1999 Mercury Mountaineers?

Out of 211 Differentials that fit 1999 Mercury Mountaineers, the following parts are the top sellers:

What’s the price range for 1999 Mercury Mountaineer Differentials?

The prices of Differentials for the 1999 Mercury Mountaineer range from $1.29 up to $1,481.99 for the most premium parts.

What is the average price of a Differential for a 1999 Mercury Mountaineer?

The average price for Differentials for the 1999 Mercury Mountaineer is $200.51. 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 1999 Mercury Mountaineer?

The cheapest 1999 Mercury Mountaineer Differentials we carry are:

Does Advance Auto Parts sell Differentials for any other 1999 Mercury models?

Yes. We stock Differentials for 5 other popular 1999 Mercury models. Some of the most popular are 1999 Cougar Differentials, 1999 Grand Marquis Differentials, 1999 Tracer Differentials, 1999 Mystique Differentials, and 1999 Sable Differentials.

What are the top-rated Differentials that fit the 1999 Mercury Mountaineer?

The one 1999 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 1999 Mercury Mountaineer?

As of 6/2/26, these are some of the most in-demand types of Differentials for a 1999 Mercury Mountaineer:

Can I get help with 1999 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.