1977 Mercury Comet Differentials

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Keep Your 1977 Mercury Comet in Top Shape with Quality Differentials

Whether you’re repairing or upgrading your Differential, using high-quality parts is key to keeping your 1977 Mercury Comet looking sharp and performing at its best. At Advance Auto Parts we carry a wide selection of dependable options, including Differential Pinion Seals, 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. For example, Motive Gear Differentials start at just $2.99 with an average 4.1 star rating. With over 12 reviews and a solid 4.0 star average, you can shop with confidence knowing other Mercury Comet owners approve.

Competitive Prices and Extensive Inventory

The average price for a 1977 Mercury Comet Differential at Advance Auto Parts is around $269.35, with a range that starts at $2.99 and goes up to $1,211.99. With 322 options in stock from 10 trusted brands, finding the right fit is easy. Popular picks like Yukon Gear 3 Qt – Penzoil 80W90 Conventional Gear Oil, 15002, Felpro Differential Carrier Gasket Oval Shaped 10 Bolt Hole Gasket, RDS 13270, and Yukon Gear Crush Sleeve, 33093 start at just $5.49 and offer a great balance of form and function.

Explore Related Parts

While you’re upgrading or replacing your Differential, don’t forget to check out other key components like Drive Shafts and Axles and Universal Joints. At Advance Auto Parts, we’re here to help you keep your 1977 Mercury Comet in peak condition, inside and out.

Essential 1977 Mercury Comet Differentials

Richmond Gear – Richmond Gear Differential Pinion Shaft, CSPF9 (Part No.CSPF9)

Richmond Gear Differential Pinion Shaft, CSPF9

from

$26.49
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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Schaeffler – Schaeffler Bearing – TRB (Tapered Roller Bearing), KT4 (Part No.KT4)

Schaeffler Bearing - TRB (Tapered Roller Bearing), KT4

from

$13.99
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.
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Powertrax – Powertrax Grip PRO Traction System, GT109028 (Part No.GT109028)

Powertrax Grip PRO Traction System, GT109028

from

$496.99
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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Driveworks – Driveworks Taper Bearing Set, S-A-6 (Part No.S-A-6)

Driveworks Taper Bearing Set, S-A-6

from

$11.99
Value-priced bearing meets all cataloged application requirements.
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Yukon Gear – "Yukon Gear Fill Plug For Ford 9"", 1/2"" Thread, 33539" (Part No.33539)

"Yukon Gear Fill Plug For Ford 9"", 1/2"" Thread, 33539"

from

$10.99
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.
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National – National Multi-Purpose Bearing, R-1535-TAV (Part No.R-1535-TAV)

National Multi-Purpose Bearing, R-1535-TAV

from

$42.49
Manufactured with premium-grade steel, National cylindrical outer races are designed and engineered to meet OE specifications.
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Yukon Gear – Yukon Gear Trac Loc Friction Plate, 4 Tab, 16177 (Part No.16177)

Yukon Gear Trac Loc Friction Plate, 4 Tab, 16177

from

$21.99
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. You can count on Yukon to fulfill all your differential small parts needs.
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Yukon Gear – "Yukon Gear 9"" Ford Pinion Nut, 35 Spline Large Pinion Oversize, 33161" (Part No.33161)

"Yukon Gear 9"" Ford Pinion Nut, 35 Spline Large Pinion Oversize, 33161"

from

$26.99
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.
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Yukon Gear – "Yukon Gear Trac-Loc For Ford 8"" Wtih 28 Spline Axles – Street Design, 26002" (Part No.26002)

"Yukon Gear Trac-Loc For Ford 8"" Wtih 28 Spline Axles - Street Design, 26002"

from

$889.99
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.
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Yukon Gear – "Yukon Gear Positraction Internals for Ford 8""/9"" with 28 Spline Axles, 2-Pinion Design, 16022" (Part No.16022)

"Yukon Gear Positraction Internals for Ford 8""/9"" with 28 Spline Axles, 2-Pinion Design, 16022"

from

$285.99
This kit replaces the internals of a positraction unit for popular Ford diffs with 28 spline axles. Yukon uses higher quality materials and better techniques than OEM to ensure longer lasting gears. This kit does not include clutches.
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Yukon Gear – "Yukon Gear Outer Oil Slinger For Ford 7.5"", 8.8"", 9"", 10.25"", 33022" (Part No.33022)

"Yukon Gear Outer Oil Slinger For Ford 7.5"", 8.8"", 9"", 10.25"", 33022"

from

$8.99
“Replacement outer oil slinger for Ford 7.5″”, 8.8″”, 9″”, 10.25″”, Nissan Titan rear, Dana 44 Rubicon & 44 JK non-Rubicon.”
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Schaeffler – Schaeffler Shaft Seal, SS2934 (Part No.SS2934)

Schaeffler Shaft Seal, SS2934

from

$13.99
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.
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Richmond Gear – Richmond Gear Differential Gear Install Kit, 83-1011-B (Part No.83-1011-B)

Richmond Gear Differential Gear Install Kit, 83-1011-B

from

$48.99
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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Yukon Gear – "Yukon Gear Master Overhaul Kit for Ford 8"" Differential with HD Pinion Support, 14049" (Part No.14049)

"Yukon Gear Master Overhaul Kit for Ford 8"" Differential with HD Pinion Support, 14049"

from

$297.99
Yukon Master Overhaul Kits give you all the high-quality parts you need to start and finish every differential job. Yukon offers more tailor-made kits than any other manufacturer in the industry to meet your specific installation needs. This kit uses Timken bearings and races along with high quality seals and small parts. Yukon Master Overhaul Kits are the most comprehensive and complete kits on the market because Yukon does extensive research to ensure that every kit has everything you need for your application.
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Yukon Gear – "Yukon Gear Purple Aluminum Pinion Support for 9"" Ford Daytona, 32161" (Part No.32161)

"Yukon Gear Purple Aluminum Pinion Support for 9"" Ford Daytona, 32161"

from

$219.99
Yukon heavy duty pinion supports feature upgraded materials and a larger design than OEM to provide heavy duty strength in racing and off-road applications
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Yukon Gear – "Yukon Gear Trac Loc Spring for Ford 9"" & 8, 33518" (Part No.33518)

"Yukon Gear Trac Loc Spring for Ford 9"" & 8, 33518"

from

$8.99
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.
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Yukon Gear – "Yukon Gear Crush Sleeve Eliminator Kit for Ford 9"", 55041" (Part No.55041)

"Yukon Gear Crush Sleeve Eliminator Kit for Ford 9"", 55041"

from

$68.99
Yukon shim kits are precision machined and tailored for each individual application to ensure you have the right shims for every set up.
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Yukon Gear – "Yukon Gear Standard Open Spider Gear Kit, Ford 9"", 31 Spline, 4-Pinion Design, 16034" (Part No.16034)

"Yukon Gear Standard Open Spider Gear Kit, Ford 9"", 31 Spline, 4-Pinion Design, 16034"

from

$317.99
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.
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Yukon Gear – "Yukon Gear Steel Spool for Ford 9"" with 35 Spline Axles, Small Bearing, 32098" (Part No.32098)

"Yukon Gear Steel Spool for Ford 9"" with 35 Spline Axles, Small Bearing, 32098"

from

$404.99
Yukon Full Spools are a cost-effective way to convert a diff to 100% lockup. Installation is easy as they install in place of your differential carrier assembly. Each Yukon spool is made from high-quality 8620 steel and heat treated for additional strength. A spool is an outstanding choice for dedicated off-road and drag racing vehicles only.
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Motive Gear – Motive Gear Differential Ring and Pinion, F9-620A (Part No.F9-620A)

Motive Gear Differential Ring and Pinion, F9-620A

from

$184.99
Motive Gear Differential Ring and Pinion, F9-620A.
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Yukon Gear – "Yukon Gear Pinion Gear and Thrust Washer for 8"" and 9"" Ford, Model 20, and 7.25"" Chrysler, 33301" (Part No.33301)

"Yukon Gear Pinion Gear and Thrust Washer for 8"" and 9"" Ford, Model 20, and 7.25"" Chrysler, 33301"

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.
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Yukon Gear – "Yukon Gear 3.062"" Side Adjuster for Ford 9"", 32139" (Part No.32139)

"Yukon Gear 3.062"" Side Adjuster for Ford 9"", 32139"

from

$94.99
Yukon Gear & Axle dropouts are heavy duty. They feature upgraded nodular iron construction and a larger-than-OEM design to provide unrivaled strength and reliability in racing and off-road applications.
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Yukon Gear – "Yukon Gear Dana 44, Ford 8"" / 9"", and Model 20 Side Gear Thrust Washer Replacement, 33283" (Part No.33283)

"Yukon Gear Dana 44, Ford 8"" / 9"", and Model 20 Side Gear Thrust Washer Replacement, 33283"

from

$5.99
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.
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Yukon Gear – "Yukon Gear Master Overhaul Kit For Ford 9"" LM104911 Differential, 35 Spline Pinion, 14063" (Part No.14063)

"Yukon Gear Master Overhaul Kit For Ford 9"" LM104911 Differential, 35 Spline Pinion, 14063"

from

$544.99
Yukon Master Overhaul kits give you all the high quality parts you need to start & finish every differential job. Yukon offers more tailor-made kits than any other manufacturer in the industry to meet your specific installation needs. This kit uses Timken bearings and races along with high quality seals and small parts. Included in this kit are carrier bearings and races, pinion bearings and races, pinion seal, complete shim kit, ring gear bolts, pinion nut, crush sleeve (if applicable), oil baffles and slingers (if applicable), Thread locking compound, marking compound with brush, and gasket. Yukon’s Master Overhaul kits are the most comprehensive and complete kits on the market. They do extensive research to ensure that every kit is specially tailored to your application.
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Yukon Gear – "Yukon Gear Grizzly Locker For Ford 9"" Differential With 35 Spline Axles, Racing Design, For Load Bolt D/O, 28030" (Part No.28030)

"Yukon Gear Grizzly Locker For Ford 9"" Differential With 35 Spline Axles, Racing Design, For Load Bolt D/O, 28030"

from

$1211.99
“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. This is a race unit designed for extreme off road use or racing. 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.”
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Yukon Gear – "Yukon Gear O-ring for 9"" Ford, 30028" (Part No.30028)

"Yukon Gear O-ring for 9"" Ford, 30028"

from

$14.99
Yukon Mighty Seals use the latest design and manufacturing technologies to produce a precision fit that seals tight and lasts for years to come.
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Yukon Gear – "Yukon Gear 1.250"" Pinion Adaptor Sleeve (Stock Pinion Into Large Support), 32239" (Part No.32239)

"Yukon Gear 1.250"" Pinion Adaptor Sleeve (Stock Pinion Into Large Support), 32239"

from

$74.99
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.
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Motive Gear – Motive Gear Differential Housing, 26306 (Part No.26306)

Motive Gear Differential Housing, 26306

from

$533.99
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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Most Popular Differential Pinion Seals for 1977 Mercury Comets

Enhance your 1977 Mercury Comet with one of the 2 Differential Pinion Seals we have in stock, starting at just $12.99.

Yukon Gear – "Yukon Gear 8"" Ford Pinion Seal, 30180" (Part No.30180)

"Yukon Gear 8"" Ford Pinion Seal, 30180"

from

$24.99
Yukon Mighty Seals use the latest design and manufacturing technologies to produce a precision fit that seals tight and lasts for years to come.
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Motive Gear – Motive Gear Differential Pinion Seal, 7044NA (Part No.7044NA)

Motive Gear Differential Pinion Seal, 7044NA

from

$12.99
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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Best-Selling 1977 Mercury Comet Differential Bearings

Upgrade your Comet with one of our 2 best-selling Differential Bearings.

Yukon Gear – "Yukon Gear One (1) Specialty Bearing Race To Adapt Small Bearing Journal Into 3.25"" Dropout, 32157" (Part No.32157)

"Yukon Gear One (1) Specialty Bearing Race To Adapt Small Bearing Journal Into 3.25"" Dropout, 32157"

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.
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Schaeffler – Schaeffler Bearing – TRB (Tapered Roller Bearing), KT45 (Part No.KT45)

Schaeffler Bearing - TRB (Tapered Roller Bearing), KT45

from

$21.99
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.
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Top-Quality Differential Oil for 1977 Mercury Comets

Choose a high-quality OEM or aftermarket Differential Oil for Mercury Comets and enjoy top-notch performance from $44.99.

Yukon Gear – Yukon Gear 3 Qt – Penzoil 80W90 Conventional Gear Oil, 15002 (Part No.15002)

Yukon Gear 3 Qt - Penzoil 80W90 Conventional Gear Oil, 15002

from

$44.99
Union 76 gear oil is a conventional non-synthetic 80W90 formulation designed for all types of differentials.
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Yukon Gear – "Yukon Gear Redline Synthetic ""Shock Proof"" Oil – 4 Quarts, 15004" (Part No.15004)

"Yukon Gear Redline Synthetic ""Shock Proof"" Oil - 4 Quarts, 15004"

from

$137.99
Redline Heavy Shockproof Gear Oil is formulated to provide lasting protection.
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Our Top Pick for a 1977 Mercury Comet Differential Cover

Invest in a durable Differential Cover for your 1977 Mercury, knowing you’re getting trusted brands and expert craftsmanship.

Yukon Gear – "Yukon Gear Outer Oil Slinger For Ford 7.5"", 8.8"", 9"", 10.25"", 33022" (Part No.33022)

"Yukon Gear Outer Oil Slinger For Ford 7.5"", 8.8"", 9"", 10.25"", 33022"

from

$8.99
“Replacement outer oil slinger for Ford 7.5″”, 8.8″”, 9″”, 10.25″”, Nissan Titan rear, Dana 44 Rubicon & 44 JK non-Rubicon.”
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Rear Differential Cover Gaskets for 1977 Mercury Comets

Make a smart move for your 1977 Mercury Comet with products all priced from $6.49 to $11.99.

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

"Yukon Gear 9"" Ford Gasket, 23012"

from

$11.99
“9”” Ford gasket. EXTERNAL SUPPLY>FDO>BACK ROOM-FDO>APPLICATION SPECIFIC from Yukon Gear”
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Yukon Gear – "Yukon Gear 8"" Dropout Housing Gasket, 23010" (Part No.23010)

"Yukon Gear 8"" Dropout Housing Gasket, 23010"

from

$11.99
“8”” dropout housing gasket. EXTERNAL SUPPLY>FDO>BACK ROOM-FDO>APPLICATION SPECIFIC from Yukon Gear”
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Victor Reinz – Victor Reinz Differential Cover Gasket, 71-14821-00 (Part No.71-14821-00)

Victor Reinz Differential Cover Gasket, 71-14821-00

from

$6.49
With Victor Reinz gaskets, you can be sure you are getting sealing solutions that deliver OE quality gasket technology and engineering. That is because Victor Reinz is an original equipment supplier and the trusted choice of manufacturers the world over, offering broad coverage for foreign and domestic cars and trucks. In Victor Reinz gasket sets, you get the right combination of components needed for fast, long-lasting repairs.
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Top-Rated Differential Brands For Your 1977 Mercury Comet

When it comes to finding the perfect Differential for your 1977 Mercury Comet, Advance Auto Parts has you covered with a wide selection of high-quality OEM and aftermarket options from 10 trusted brands. We carry the most popular Differential brands including Motive Gear, and more, all known for their exceptional customer ratings (average brand rating of 4.1 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 1977 Mercury Comet, providing peace of mind with parts that meet or exceed OEM standards.

Popular Motive Gear 1977 Mercury Comet Differentials

If you’re looking for a top-quality Differential for your 1977 Mercury Comet, Advance Auto Parts has exactly what you need with our selection of Motive Gear Differentials. We have 2 Motive Gear Differentials in stock for this fitment, all known for their durability and precision fit. With prices starting at just $2.99 and an average cost of $4.99, you’ll find the perfect Differential for your needs and budget. Motive Gear Differentials for the 1977 Mercury Comet come highly rated, with over 2 customer reviews and an impressive average rating of 4.1 stars. Choosing a Motive Gear Differential from Advance Auto Parts is a smart move to ensure quality and value for your vehicle.
Motive Gear Differential Pinion Nut, 379570S
from $6.99
(1)
Motive Gear Differential Pinion Nut, 379570S
“If a pinion nut is ever removed from the pinion shaft, it is recommended NOT to reuse it. Replace it with a BRAND NEW nut, even if the old nut is rel”
Motive Gear Differential Crush Sleeve, 3507575
from $2.99
(1)
Motive Gear Differential Crush Sleeve, 3507575
“High quality, would buy again”

FAQs for 1977 Mercury Comet Differentials

What are the best-selling Differentials for 1977 Mercury Comets?

Out of 322 Differentials that fit 1977 Mercury Comets, the following parts are the top sellers:

What’s the price range for 1977 Mercury Comet Differentials?

The prices of Differentials for the 1977 Mercury Comet range from $2.99 up to $1,211.99 for the most premium parts.

What is the average price of a Differential for a 1977 Mercury Comet?

The average price for Differentials for the 1977 Mercury Comet is $269.35. 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 Comet model years?

Yes, we carry Differentials for 15 model years of Mercury Comets between 1960 and 1976. The following model years are the most popular for Differential purchases: 1976, 1975, 1974, 1973, 1972, 1971, 1969, 1968, and 1967.

Does Advance Auto Parts sell Differentials for any other 1977 Mercury models?

Yes. We stock Differentials for 5 other popular 1977 Mercury models. Some of the most popular are 1977 Cougar Differentials, 1977 Grand Marquis Differentials, 1977 Capri Differentials, 1977 Marquis Differentials, and 1977 Monarch Differentials.

What types of Differentials do you sell for my 1977 Mercury Comet?

As of 8/2/26, these are some of the most in-demand types of Differentials for a 1977 Mercury Comet:

Can I get help with 1977 Mercury Comet 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 Comet Differentials?

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