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 Ring Gear Bolts, Differential Pinion Seals, and Differential Bearings. 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 Powertrax. For example, Motive Gear Differentials start at just $2.79 with an average 4.0 star rating. National and Powertrax offer similar pricing and quality, backed by strong customer feedback. With over 15 reviews and a solid 5 star average, you can shop with confidence knowing other Mercury Comet owners approve.

Explore Related Parts

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

Essential 1977 Mercury Comet Differentials

Yukon Gear – Pilot Bearing Retainer For Ford 9" (Part No.33255)

Pilot Bearing Retainer For Ford 9"

from

$11.99
Pilot bearing retainer for Ford 9″.

Product Features:
  • Pilot bearing retainer for Ford 9″
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Yukon Gear – Pinion Depth Shims For Ford 9" With 7/16" Studs (Part No.55057)

Pinion Depth Shims For Ford 9" With 7/16" Studs

from

$76.99
Product Features:
  • Pinion depth shim kit
  • Fits Ford 9″ with 7/16″ pinion support bolts
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Yukon Gear – Bearing Install Kit For Ford 8" Differential With Aftermarket Positraction Or Locker (Part No.11112)

Bearing Install Kit For Ford 8" Differential With Aftermarket Positraction Or Locker

from

$236.99
Yukon Bearing installation kits are perfect for shops & builders who have shims on the shelf and are looking to save cost over a Master Overhaul kit. This kit uses Timken bearings and races along with all high quality small parts. kit includes carrier bearings and races, pinion bearings and races, pinion seal, crush sleeve (if applicable), oil baffles and slingers (if applicable), marking compound and brush. Yukon does extensive research for each application to make sure your kit will arrive with all the correct parts you need to install your ring & pinion set.

Product Features:
  • Fits Ford 8″ with aftermarket positraction
  • Included are carrier bearings and races, pinion bearings and races, pinion seal, crush sleeve, marking compound and brush.
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Yukon Gear – Trac Loc Steel Clutch Plate, 4 Tab (Part No.16178)

Trac Loc Steel Clutch Plate, 4 Tab

from

$8.99
Product Features:
  • Steel clutch plate
  • Fits Ford 8″ and 9″ Trac Loc
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Yukon Gear – Crush Sleeve (Part No.33093)

Crush Sleeve

from

$10.99
Crush Sleeve for Model 35, Chrysler 7.25″, 8.25″ Ford 8″ & GM 7.75″. Approx 0.495″ long.

Product Features:
  • Crush sleeve for AMC Model 35, Chrysler 7.25″ and 8.25″, Ford 8″ and GM 7.75″
  • 0.495″ tall
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Yukon Gear – Adjuster Lock Bolt 3.062" & 3.250" Ford 9" Drop Out (Part No.32149)

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

from

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

Product Features:
  • Side adjuster lock bolt
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Motive Gear – Ring Gear Bolt (Part No.D8OZ4216B)

Ring Gear Bolt

from

$1.99


Product Features:
  • BOLT 9″ FORD OPEN R.G. SAME AS M-4216A200
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Yukon Gear – 0.260" Diameter Cross Pin Roll Pin For 8.75" Chrysler, 8", 9" Ford, And Model 20 And 35 (Part No.33334)

0.260" Diameter Cross Pin Roll Pin For 8.75" Chrysler, 8", 9" Ford, And Model 20 And 35

from

$5.99
0.260″ diameter cross pin roll pin for 8.75″ Chrysler, 8″, 9″ Ford, and Model 20 and 35.

Product Features:
  • Roll pin for Chrysler 8.75″, Ford 8″ and 9″, AMC Model 20 and Model 35
  • 0.260″ diameter
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Motive Gear – Differential Gear Install Kit (Part No.F8IK)

Differential Gear Install Kit

from

$44.49
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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Powertrax – Grip LOK Traction System (Part No.LK109028)

Grip LOK Traction System

from

$668.99
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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Mr. Gasket – Rear End Gasket – Ford 9" – Blend Of Nitrile Rubber And Fiber For Excellent Sealing And Durability (Part No.82)

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

from

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

Product Features:
  • .047″ thick cellulose/nitrile composite gasket material
  • Precision die cut
  • Reusable
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Dorman – Differential Pinion Yoke Assembly (Part No.697-527)

Differential Pinion Yoke Assembly

from

$177.99
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 – The Carrier Bearing Puller (Part No.56034)

The Carrier Bearing Puller

from

$689.99
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 most standard one ton applications. This unit is works with differentials up to one-ton applcations. It is not compatible with 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
  • Not compatible with Dana 70HD, Dana 80, Ford 10.25″ and 10.5″ or Gm and Chrysler 11.5″ applications
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Yukon Gear – Star Washers, 3.250" Ford 9" Drop Out New Design Only (Part No.32144)

Star Washers, 3.250" Ford 9" Drop Out New Design Only

from

$4.99
STAR washers, 3.250″ Yukon Ford 9″ Drop Out new design ONLY.

Product Features:
  • Star washer
  • Fits Ford 9″
  • 3.250″ designs only
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Yukon Gear – Fine Thread Pinion Support Bolt (Aftermarket Aluminum Only) For 9" Ford (Part No.33243)

Fine Thread Pinion Support Bolt (Aftermarket Aluminum Only) For 9" Ford

from

$5.99
Fine thread pinion support bolt (aftermarket aluminum only) for 9″ Ford.

Product Features:
  • Pinion support bolt for Ford 9″
  • 3/8″ x 24 thread
  • 1.5″ long
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Yukon Gear – 8" Ford O-Ring (Part No.30027)

8" Ford O-Ring

from

$9.99
8″ Ford O-ring.

Product Features:
  • Pinion support o-ring
  • Fits Ford 8″
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Yukon Gear – Trac Loc Clutch Guide For 9" Ford (Part No.33250)

Trac Loc Clutch Guide For 9" Ford

from

$4.99
Trac Loc clutch guide for 9″ Ford.

Product Features:
  • Clutch guide
  • Fits Ford 8″ and 9″
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Yukon Gear – 8" Ford Pinion Seal (Part No.30180)

8" Ford Pinion Seal

from

$24.99
8″ Ford pinion seal.Yukon Mighty seal.

Product Features:
  • Pinion seal
  • Fits Ford 8″
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Motive Gear – Differential Lock Thrust Block (Part No.D3SZ4211A)

Differential Lock Thrust Block

from

$47.49
Motive Gear offers some of the toughest drive train components on the market today. If you are looking for the largest line of performance ring and pinion gear options available with gear sets in a wide range of ratios for nearly every application, both on and off-road, check out Motive Gear. Motive Gear products can be found in the winner’s circle at racing events worldwide. The superior quality of Motive Gear components is the result of years of racing development, outstanding design and state-of-the-art manufacturing methods. Extensive testing is performed on all products by our in-house engineers.
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Yukon Gear – Outer Oil Slinger For Ford 7.5", 8.8", 9", 10.25" (Part No.33022)

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

from

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

Product Features:
  • Outer oil slinger for Ford 10.25″, 7.5″, 8.8″ and 9″ also Jeep JK and Nissan Titan rear
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Richmond Gear – Differential Cross Shaft (Part No.CSPF9)

Differential Cross Shaft

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!

Product Features:
  • For over 80-years, the Richmond Double-Diamond logo has represented some of the highest quality gears in the racing industry. Winners Run Richmond!
  • The superior quality of Richmond gearsets is a result of outstanding design, world class manufacturing and an extensive testing process that is performed on all products.
  • Richmond performance gearsets have been winners for decades at: NHRA, NMRA, NMCA, Daytona 500, WISSOTA and U.S. Nationals.
  • Richmond Gear is a leading manufacturer of high performance ring and pinion gearsets and drivetrain components, backed by a two year warranty.
  • Engineered to perform faster and be more reliable, Richmond performance drivetrain products are the result of a continuous research and development program combined with state-of-the-art manufacturing capabilities.
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Yukon Gear – High Performance Ring & Pinion Gear Set For Ford 9" In A 5.67 Ratio (Part No.24389)

High Performance Ring & Pinion Gear Set For Ford 9" In A 5.67 Ratio

from

$484.99
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 Ford 9″
  • 9.00″ ring gear diameter
  • 28 spline pinion
  • 10 ring gear bolts
  • 5.67 ratio
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National – Shaft Repair Sleeve (Part No.99193)

Shaft Repair Sleeve

from

$43.99
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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Motive Gear – Differential Pinion Solid Spacer Kit w/Shims (Part No.4105)

Differential Pinion Solid Spacer Kit w/Shims

from

$22.79


Product Features:
  • FORD 9″ SOLID SPACER KIT
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Yukon Gear – Pinion Install Kit For Ford 8" Differential (Part No.13040)

Pinion Install Kit For Ford 8" Differential

from

$251.99
Yukon Pinion installation kits are a terrific solution for gear installation on lower mileage vehicles where the carrier bearings & races can be reused. This kit uses Timken bearings and races along with a high quality pinion seal and small parts. Included in this kit are the pinion bearings and races, pilot bearing (if applicable), crush sleeve (if applicable), complete pinion shim kit, thread locker, and marking compound with brush. Yukon does extensive research for each application to make sure your kit will arrive with all the correct parts you need to install your pinion gear.

Product Features:
  • Fits Ford 8″
  • Included are pinion bearings and races, pinion seal, pinion nut, crush sleeve, complete pinion shim kit, and marking compound with brush.
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Yukon Gear – Bearing Race Driver (Part No.56019)

Bearing Race Driver

from

$219.99
Bearing race driver. No return.

Product Features:
  • Bearing race driver
  • Fits LM104911 race
  • All steel construction
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Yukon Gear – Pilot Bearing For Ford 8" (Part No.18043)

Pilot Bearing For Ford 8"

from

$40.99
9.25 Chrysler FRONT PINION KIT , 03 & UP DODGE TRUCK .

Product Features:
  • Pilot bearing
  • Fits Ford 8″
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Yukon Gear – Dana 44, Ford 8" / 9", And Model 20 Side Gear Thrust Washer Replacement (Part No.33283)

Dana 44, Ford 8" / 9", And Model 20 Side Gear Thrust Washer Replacement

from

$5.99
Product Features:
  • Side gear thrust washer for Ford 8″, Ford 9″ and AMC Model 20
  • 0.030″ thick
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Most Popular Differential Ring Gear Bolts for 1977 Mercury Comets

Enhance your 1977 Mercury Comet with one of the 6 Differential Ring Gear Bolts we have in stock, starting at just $1.99.

Yukon Gear – Ford 8" & 9" Standard Open, Ag, & Detroit Locker Ring Gear Bolt (Part No.33058)

Ford 8" & 9" Standard Open, Ag, & Detroit Locker Ring Gear Bolt

from

$5.99
Ford 8″ & 9″ standard Open, AG, & Detroit locker ring gear bolt. 7/16″ head, .925″ long.

Product Features:
  • Ring gear bolt for Ford 8″ and 9″
  • For use with standard open carrier, Auburn Gear limited slip and Detroit Locker
  • 7/16″ head
  • .925″ long
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Yukon Gear – Ford 8" & 9" Standard Open, Ag, & Detroit Locker Ring Gear Bolt (Part No.33043)

Ford 8" & 9" Standard Open, Ag, & Detroit Locker Ring Gear Bolt

from

$5.99
Ford 8″ & 9″ standard Open, AG, & Detroit locker ring gear bolt, 1.0″ long, Ford.

Product Features:
  • Ring gear bolt for Ford 8″ and 9″
  • For use with standard open carrier, Auburn Gear limited slip and Detroit Locker
  • 1.0″ long
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Yukon Gear – Ford 8" & 9" Tracloc Ring Gear Bolt (Part No.33044)

Ford 8" & 9" Tracloc Ring Gear Bolt

from

$4.99
Ford 8″ & 9″ TracLoc ring gear bolt, 1-1/4″ long.

Product Features:
  • Ring gear bolt for Ford 8″ and 9″
  • For use with Trac Loc limited slip
  • 1.25″ long
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Motive Gear – Ring Gear Bolt (Part No.D8OZ4216B)

Ring Gear Bolt

from

$1.99


Product Features:
  • BOLT 9″ FORD OPEN R.G. SAME AS M-4216A200
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ARP Auto Racing – For Use With Ford 9" Using 5/8"Socket, 0.94"L Under Head, 7/16"-20, 12Point Head (Part No.250-3002)

For Use With Ford 9" Using 5/8"Socket, 0.94"L Under Head, 7/16"-20, 12Point Head

from

$43.99
The tremendous shock loads generated at launch by most any drag racing vehicle equipped with today sticky tire compounds or the acceleration and deceleration of oval track cars put considerable strain on the ring gear. For this reason, the fastener experts at ARP have developed the Pro Series ring gear bolts. they are forged from premium grade 8740 chrome moly steel and are heat treated to a nominal rating of 200,000 PSI tensile strength. Specially hardened, precision ground washers are included where required. Available to fit most any ring gear setup ranging from popular 9 Inch Ford GM 10 and 12 bolt rear ends to the beefy strange differentials found in top fuel and funny car applications.

Product Features:
  • Forged From Premium Grade 8740 Chrome Moly Steel
  • Heat Treated
  • Nominally Rated At 200,000 PSI Tensile Strength
  • Specially Hardened, Precision Ground Washers
  • 0.95″ Underhead Length
  • 200,000 PSI
  • Sold As A Set
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Yukon Gear – Trac Loc Ring Gear Bolt Washer For 8" And 9" Ford (Part No.33245)

Trac Loc Ring Gear Bolt Washer For 8" And 9" Ford

from

$3.99
Trac Loc ring gear bolt washer for 8″ and 9″ Ford.

Product Features:
  • Ring gear bolt for Ford 8″ and 9″
  • For Trac Loc positraction applications only
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Best-Selling 1977 Mercury Comet Differential Pinion Seals

Upgrade your Comet with one of our 3 best-selling Differential Pinion Seals, earning an average 5 stars rating across 2 reviews.

National – Multi-Purpose Seal (Part No.8181NA)

Multi-Purpose Seal

from

$12.99
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:
  • Design type: spring loaded; multi-lip
  • Temperature range: -40 Deg. F to 225 Deg. F / -40 Deg. C to 107 Deg. C
  • Good low temperature capability
  • Low swell in hydrocarbon fluids
  • Delivers quality and reliable performance for every type of repair
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Yukon Gear – 8" Ford Pinion Seal (Part No.30180)

8" Ford Pinion Seal

from

$24.99
8″ Ford pinion seal.Yukon Mighty seal.

Product Features:
  • Pinion seal
  • Fits Ford 8″
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Motive Gear – Differential Pinion Seal (Part No.7044NA)

Differential Pinion Seal

from

$12.99
All Motive Gear products are engineered for their specific application and manufactured in state of the art facilities. All of our products undergo rigid quality control processes to insure proper fit, performance and longevity. Motive Gear products can be found in the winners circle at NHRA, IHRA, NMRA, NMCA, SODA, SCORE, BITD, Ultra-4 and NASCAR events because we offer unmatched selection and quality demanded by racers and their crew chiefs – the same quality and selection demanded by DIY customers and top mechanics. With four warehouses strategically located across North America, most Motive Gear orders arrive within 2-4 days. Win with Motive Gear!
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Top-Quality Differential Bearings for 1977 Mercury Comets

Choose a high-quality OEM or aftermarket Differential Bearing for Mercury Comets and enjoy top-notch performance from $11.99.

Yukon Gear – Pilot Bearing Retainer For Ford 9" (Part No.33255)

Pilot Bearing Retainer For Ford 9"

from

$11.99
Pilot bearing retainer for Ford 9″.

Product Features:
  • Pilot bearing retainer for Ford 9″
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Top Picks for 1977 Mercury Comet Differential Oil

Invest in one of our 5 durable Differential Oil for your 1977 Mercury, knowing you’re getting trusted brands and expert craftsmanship.

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
3 Qt. Penzoil 80W90 conventional gear Oil. W/ bottle of Posi additive.

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
3 Qt. Penzoil 80W90 conventional gear Oil.

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

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

Redline Synthetic "Shock Proof" Oil - 3 Quarts

from

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

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

Redline Synthetic "Shock Proof" Oil - 4 Quarts

from

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

Product Features:
  • Includes four quarts of Redline Shockproof oil
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Rear Differential Cover Gaskets for 1977 Mercury Comets

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

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

9" Ford Gasket

from

$11.99
9″ Ford gasket.

Product Features:
  • Dropout gasket
  • Fits Ford 9″
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Yukon Gear – 8" Dropout Housing Gasket (Part No.23010)

8" Dropout Housing Gasket

from

$11.99
8″ dropout housing gasket.

Product Features:
  • Dropout gasket
  • Fits Ford 8″
See More

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 Powertrax, National, and Motive Gear, and more, all known for their exceptional customer ratings (average brand rating of 4.7 stars) and competitive prices, as low as $2.79. 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 Powertrax 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 Powertrax Differentials. We have 1 Powertrax Differentials in stock for this fitment, all known for their durability and precision fit. With prices starting at just $551.99, you’ll find the perfect Differential for your needs and budget. Powertrax Differentials for the 1977 Mercury Comet come highly rated, with over 1 customer reviews and an impressive average rating of 4.7 stars. Choosing a Powertrax Differential from Advance Auto Parts is a smart move to ensure quality and value for your vehicle.
No-Slip Traction System
from $551.99
(1)
No-Slip Traction System
“Installed, no issues, works great.”

Top-Quality National 1977 Mercury Comet Differentials

For those in search of a high-quality Differential for their 1977 Mercury Comet, Advance Auto Parts offers a great selection of National Differentials. With 1 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 $12.99, giving you a range of options to suit your budget. Backed by over 2 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 $12.99
(2)
Multi-Purpose Seal
“Worked great on this 1966 Mustang w/ 8″ rear end.”

FAQs for 1977 Mercury Comet Differentials

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

Out of 336 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 $1.99 up to $1,566.99 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 $277.76. 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.

What are the cheapest Differentials for my 1977 Mercury Comet?

The cheapest 1977 Mercury Comet Differentials we carry are:

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 are the top-rated Differentials that fit the 1977 Mercury Comet?

The one 1977 Mercury Comet Differential we have in stock is the Ring Gear Bolt. It costs $1.99.

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

As of 3/1/26, 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.