1978 GMC C25 Differentials

Keep Your 1978 GMC C25 in Top Shape with Quality Differentials

Whether you’re repairing or upgrading your Differential, using high-quality parts is key to keeping your 1978 GMC C25 looking sharp and performing at its best. At Advance Auto Parts we carry a wide selection of dependable options, including Differential Covers, Differential Bearings, and Rear Differential 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 Richmond Gear, National, and Valvoline. For example, Richmond Gear Differentials start at just $350.99 with an average 4.5 star rating. National and Valvoline offer similar pricing and quality, backed by strong customer feedback. With over 252 reviews and a solid 4 star average, you can shop with confidence knowing other GMC C25 owners approve.

Competitive Prices and Extensive Inventory

The average price for a 1978 GMC C25 Differential at Advance Auto Parts is around $213.86, with a range that starts at $0.91 and goes up to $1,141.99. With 138 options in stock from 14 trusted brands, finding the right fit is easy. Popular picks like DEXRON – VI ATF Full Synthetic Automatic Transmission Fluid, 1 Quart, DEX/MERC ATF Conventional Automatic Transmission Fluid, 1 Quart, and Differential Shaft Lock Bolt start at just $6.79 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 1978 GMC C25 in peak condition, inside and out.

Essential 1978 GMC C25 Differentials

Richmond Gear – Differential Cross Shaft (Part No.80-0269-1)

Differential Cross Shaft

from

$64.99
Richmond Gear is the leading manufacturer of professional quality, high-performance drivetrain products. Our complete line of products ranges from high performance ring-and-pinion sets for serious street and racing applications to torque-hungry manual transmissions and components. Richmond Gear products have been winners both at the Daytona 500 and U.S. Nationals for decades. WINNERS RUN RICHMOND!

Product Features:
  • For over 80-years, the Richmond Double-Diamond logo has represented some of the highest quality gears in the racing industry. Winners Run Richmond!
  • The superior quality of Richmond gearsets is a result of outstanding design, world class manufacturing and an extensive testing process that is performed on all products.
  • Richmond performance gearsets have been winners for decades at: NHRA, NMRA, NMCA, Daytona 500, WISSOTA and U.S. Nationals.
  • Richmond Gear is a leading manufacturer of high performance ring and pinion gearsets and drivetrain components, backed by 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 – Mini Spool For GM 10.5" 14 Bolt Truck (Part No.32301)

Mini Spool For GM 10.5" 14 Bolt Truck

from

$287.99
Yukon mini spool for GM 10.5″ 14 bolt truck.

Product Features:
  • Fits 10.5″ GM 14 bolt truck
  • Provides 100% traction to both wheels at all times
  • Installs into standard open carrier case
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Yukon Gear – Pinion Install Kit For ’88 And Older 10.5" GM 14 Bolt Truck Differential (Part No.13058)

Pinion Install Kit For '88 And Older 10.5" GM 14 Bolt Truck Differential

from

$349.99
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 1988 and down GM 10.5″ 14 bolt truck
  • Included are pinion bearings and races, pinion seal, crush sleeve, complete pinion shim kit, and marking compound with brush.
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Yukon Gear – Bearing Race Driver (Part No.56020)

Bearing Race Driver

from

$215.99
Bearing race driver. No return.

Product Features:
  • Bearing race driver
  • Fits M802011 race
  • All steel construction
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Motive Gear – Differential Crush Sleeve (Part No.3977355)

Differential Crush Sleeve

from

$11.99


Product Features:
  • CRUSH SLEEVE 14 BOLT 10.5 3116
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Yukon Gear – 14T Pinion Gear Thrust Washer (Part No.33384)

14T Pinion Gear Thrust Washer

from

$8.99
14T pinion gear Thrust washer.

Product Features:
  • Pinion gear thrust washer
  • Fits GM 10.5″ 14 bolt truck
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Yukon Gear – Dura Grip Positraction For 10.5" GM 14 Bolt Truck, 4.10 & Down (Part No.26030)

Dura Grip Positraction For 10.5" GM 14 Bolt Truck, 4.10 & Down

from

$1110.00
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 GM 10.5″ 14 bolt truck
  • 4.10 ratio and down only
  • 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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Felpro – Axle Housing Cover Gasket: Irregular Shaped 14 Bolt Hole Gasket (Part No.RDS 55063)

Axle Housing Cover Gasket: Irregular Shaped 14 Bolt Hole Gasket

from

$8.29
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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Dorman – Help – Differential Shaft Lock Bolt (Part No.81048)

Differential Shaft Lock Bolt

from

$6.79
This differential pinion shaft lock bolt is designed to match the fit and function of the original part on specified vehicles. Made of quality materials, it is engineered for reliable performance.

Product Features:
  • Direct replacement – this differential pinion shaft lock bolt matches the fit and function of the factory part on specified years, makes and models
  • Ideal solution – this bolt is a reliable replacement for an original part that is missing or has failed due to fatigue
  • Durable construction – this part is made from quality materials to ensure reliable performance and long service life
  • Trustworthy quality – backed by team of product experts in the United States and more than a century of automotive experience
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Yukon Gear – Steel Cover For GM 10.5" 14 Bolt Truck (Part No.32345)

Steel Cover For GM 10.5" 14 Bolt Truck

from

$92.99
Product Features:
  • Fits GM 10.5″ 14 bolt truck
  • Steel
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Yukon Gear – DiffrlPinSupportBolt (Part No.33582)

DiffrlPinSupportBolt

from

$5.99
DiffrlPinSupportBolt

Powertrax – Lock Right Locker (Part No.1950-LR)

Lock Right Locker

from

$487.99
The Powertrax Lock-Right ultra-strength alloy locker’s straight-line performance is equal to a solid spool, but automatically unlocks in turns. Best suited for extreme off-road to severe on-road use, Powertrax Lock Right lockers replace the spider gears in your open differential carrier using basic tools and without affecting your ring and pinion settings. The whole job can be done in your driveway in a couple of hours, pin included! 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!

Product Features:
  • Powertrax® proves that you don’t have to choose between the superior traction of a locking differential and smooth handling and drivability of an open differential. Powertrax Lock-Right Lockers, No-Slip Traction Systems and GRIP limited slip differentials and lockers give you the best of both worlds!
  • The Powertrax® Lock-Right Locker provides outstanding traction for off-road machines and race vehicles. Powertrax No-Slip Traction Systems deliver excellent performance to street-driven cars and trucks.
  • Powertrax® lockers range from the original, Lock-Right for serious straight-line performance, to the No-Slip traction system for street-able vehicles.
  • Powertrax® 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.
  • Powertrax® = Extreme Traction Systems!
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Yukon Gear – Eaton Positraction Shim Kit For 10.5" GM 14 Bolt Truck (Part No.16113)

Eaton Positraction Shim Kit For 10.5" GM 14 Bolt Truck

from

$78.99
Eaton positraction shim kit for GM 14T.

Product Features:
  • Shim kit
  • Fits GM 10.5″ 14 bolt truck Eaton positraction
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National – Multi-Purpose Bearing (Part No.R-1581-TV)

Multi-Purpose Bearing

from

$33.99
National Oil Seals & Bearings offer a full line of premium oil seals and bearings.

Product Features:
  • PREMIUM MATERIALS — Precision manufactured using premium-grade steel for outstanding durability and performance
  • STRONG AND DURABLE — Controlled heat treatment process for strength and durability
  • OE-STYLE DESIGN — Engineered to meet OE specifications
  • COMPREHENSIVE COVERAGE — Industry-leading coverage for domestic and import applications
  • RIGOROUS TESTING — Comprehensive testing throughout design and development processes by National engineers for quality you can count on
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Pro-King – Differential Pinion Shim Kit (Part No.743B200)

Differential Pinion Shim Kit

from

$13.99
Pro-King is the leading supplier of transmission and driveline products in the aftermarket.

Product Features:
  • All products are designed to meet or exceed OE quality, form, fit and funtion.
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Motive Gear – Axle Shaft (Part No.MG1775)

Axle Shaft

from

$141.99
The Motive Gear replacement axle shaft offers an OE-quality axle shaft at a fraction of the OE cost. Manufactured from 1541H material on high-tolerance CNC equipment, this axle shaft is designed to provide a perfect fit every time.

Product Features:
  • AXLE SHAFT GM 10.5″ 30 SPL. 31 11/16″ L.H.
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Yukon Gear – Spider Gear Set For GM 10.5" 14 Bolt Truck Dura Grip Posi (Part No.16167)

Spider Gear Set For GM 10.5" 14 Bolt Truck Dura Grip Posi

from

$659.99
Yukon spider gear set for GM 10.5″ 14 bolt truck Yukon Dura Grip posi. This kit does not include clutches. This kit fits Yukon Dura Grip ONLY. Will not work with factory Gov Loc.

Product Features:
  • Spider gear kit
  • Fits GM 10.5″ 14 bolt truck with Dura Grip positraction
  • Includes two side gears, four pinion gears, cross pin shaft, roll pin and spider gear thrust washers.
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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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National – Bearing Race (Part No.HM803110)

Bearing Race

from

$20.49
Manufactured with premium-grade steel, National taper bearing cups feature crowned raceways to ensure even load distribution.

Product Features:
  • PREMIUM MATERIALS – Precision manufactured using premium-grade steel for outstanding durability and performance
  • SMOOTH ROTATION – Crowned raceways for even load distribution
  • OE-STYLE DESIGN – Engineered to meet OE specifications
  • COMPREHENSIVE COVERAGE – Industry-leading coverage for domestic and import applications
  • RIGOROUS TESTING – Comprehensive testing throughout design and development processes by National engineers for quality you can count on
See More

Yukon Gear – Standard Open Spider Gear Kit For GM 10.5" And 14T With 30 Spline Axles (Part No.16044)

Standard Open Spider Gear Kit For GM 10.5" And 14T With 30 Spline Axles

from

$315.99
Yukon standard open spider gear kit for GM 10.5″ and 14T with 30 spline axles. Yukon uses higher quality materials and better techniques than OEM to ensure a longer lasting spider gear set. All components come with a one year warranty against manufacturing defects.

Product Features:
  • Spider gear kit
  • Fits GM 10.5″ 14 bolt truck open differential
  • Includes two side gears, four pinion gears, cross pin shaft, cross pin bolt and spider gear thrust washers.
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Yukon Gear – 14T Side Gear Thrust Washer (Part No.33383)

14T Side Gear Thrust Washer

from

$7.99
14T side gear Thrust washer.

Product Features:
  • Side gear thrust washer
  • Fits GM 10.5″ 14 bolt truck
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USA Standard Gear – Master Overhaul Kit for the ’88 and Older GM 10.5" 14T Differential (Part No.37044)

Master Overhaul Kit for the '88 and Older GM 10.5" 14T Differential

from

$349.99
USA Standard Master Overhaul kits let you finish your install with confidence. This kit uses Koyo bearings and races. Included 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), threading locking compound, marking compound with brush and gasket.

Product Features:
  • Fits 1988 and down GM 10.5″ 14 bolt truck
  • Uses Koyo bearings and races
  • Included are carrier bearings and races, pinion bearings and races, pilot bearing, pinion seal, complete shim kit, pinion nut, crush sleeve, thread locker, marking compound with brush and gasket.
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Motive Gear – Differential Bearing Kit – Timken (Part No.R12RT)

Differential Bearing Kit - Timken

from

$106.99
Motive Gear Differential Bearing Kits Include Front & Rear Pinion Bearing, Pinion Seal, Carrier Bearings, Pilot Bearing Where Applicable, Gear Marking Compound, Crush Sleeve, Pinion Nut, Brush, Thread Locking Compound And Cover Gasket Or Rtv

Product Features:
  • KIT BRG & SEAL GM 12 BLT TRK 8 7/8″
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Yukon Gear – High Performance Ring & Pinion "Thick" Gear Set For 10.5" GM 14 Bolt Truck In A 4.56 Ratio (Part No.24137)

High Performance Ring & Pinion "Thick" Gear Set For 10.5" GM 14 Bolt Truck In A 4.56 Ratio

from

$505.99
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. This is a thick gear for a 4.10 & down carrier.

Product Features:
  • Fits GM 10.5″ GM 14 bolt truck
  • 10.50″ ring gear diameter
  • 30 spline pinion
  • 12 ring gear bolts
  • 4.56 ratio
  • Thick gear set for 4.11 and down carrier
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Yukon Gear – 10.5" GM 14 Bolt Truck Ring Gear Bolt (Part No.33051)

10.5" GM 14 Bolt Truck Ring Gear Bolt

from

$10.99
14T ring gear bolt 4.11 & down. 9/16″ x 18. 2.085″ overall length.

Product Features:
  • Ring gear bolt for GM 10.5″ 14 bolt truck
  • 4.11 and down ratio
  • 1/2″ x 18 thread
  • 2.085″ overall length
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FAG US – Shaft Seal (Part No.SS2776)

Shaft Seal

from

$19.79
Our wheel seals are engineered using only the highest-quality materials to meet vehicle manufacturer specificatons. We work with suppliers to design seals that meet FAG’s quality standards. Seals are designed to protect wheel end components from contamination – such as dirt, dust, and moisture – and prevent the loss of grease over the life of the bearing. The specifications for wheel seals are very demanding, and the type required depends on the specific application, position and vehicle class.

Product Features:
  • High-precision and High-quality components used in all KITs
  • Coverage of classic and new high-tech solutions for the best system coverage
See More

Powertrax – Grip LS Traction System (Part No.LS231230)

Grip LS Traction System

from

$480.99
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!
See More

Yukon Gear – Standard Open Cross Pin Shaft For Four Pinion Design For GM 10.5" 14 Bolt Truck (Part No.33405)

Standard Open Cross Pin Shaft For Four Pinion Design For GM 10.5" 14 Bolt Truck

from

$89.99
Standard Open cross pin shaft for four pinion design for GM 14T.

Product Features:
  • Cross pin shaft
  • Fits GM 10.5″ 14 bolt truck
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Most Popular Differential Covers for 1978 GMC C25s

Enhance your 1978 GMC C25 with one of the 2 Differential Covers we have in stock, starting at just $59.99.

Yukon Gear – Steel Cover For GM 10.5" 14 Bolt Truck (Part No.32345)

Steel Cover For GM 10.5" 14 Bolt Truck

from

$92.99
Product Features:
  • Fits GM 10.5″ 14 bolt truck
  • Steel
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Yukon Gear – Chrome Cover For 10.5" GM 14 Bolt Truck (Part No.32013)

Chrome Cover For 10.5" GM 14 Bolt Truck

from

$59.99
Chrome cover for GM 14T.

Product Features:
  • Fits GM 10.5″ 14 bolt truck
  • Chrome
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Best-Selling 1978 GMC C25 Differential Bearings

Upgrade your C25 with one of our 5 best-selling Differential Bearings, earning an average 4 stars rating across 10 reviews.

National – Bearing Race (Part No.382A)

Bearing Race

from

$10.99
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
See More

Driveworks – Tapered Cone Wheel Bearing Assembly (Part No.S-387-AS)

Tapered Cone Wheel Bearing Assembly

from

$18.49
Value-priced bearing meets all cataloged application requirements.

Product Features:
  • Brand may vary by location
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National – Tapered Roller Bearing Cone (Part No.LM501349)

Tapered Roller Bearing Cone

from

$19.99
Manufactured with premium-grade steel, National taper bearing cones feature crowned raceways and rollers to ensure even load distribution.

Product Features:
  • PREMIUM MATERIALS – Precision manufactured using premium-grade steel for outstanding durability and performance
  • SMOOTH ROTATION – Crowned raceways and rollers for even load distribution
  • OE-STYLE DESIGN – Engineered to meet OE specifications
  • COMPREHENSIVE COVERAGE – Industry-leading coverage for domestic and import applications
  • RIGOROUS TESTING – Comprehensive testing throughout design and development processes by National engineers for quality you can count on
See More

National – Bearing Race (Part No.LM501310)

Bearing Race

from

$8.49
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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FAG US – Cup (Part No.LM501310)

Cup

from

$9.99
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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Top-Quality Rear Differential Cover Gaskets for 1978 GMC C25s

Choose a high-quality OEM or aftermarket Rear Differential Cover Gasket for GMC C25s and enjoy top-notch performance from $3.99.

Mr. Gasket – Differential Gasket (Part No.84B)

Differential Gasket

from

$20.99
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 1964-1970 Chevrolet 8.2 inch 10 bolt & 1970-1981 GM 8.5 inch ring gear

Product Features:
  • .047″ thick cellulose/nitrile composite gasket material
  • Precision die cut
  • Reusable
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Felpro – Axle Housing Cover Gasket: Irregular Shaped 14 Bolt Hole Gasket (Part No.RDS 55063)

Axle Housing Cover Gasket: Irregular Shaped 14 Bolt Hole Gasket

from

$8.29
Fel-Pro® gaskets are specifically designed for the repair environment to deliver a reliable seal on even the most troublesome applications. Designed for imperfect sealing surfaces and manufactured with proprietary materials, you can count on Fel-Pro for innovative sealing solutions for the real-world repair environment.

Product Features:
  • Meets or exceeds all original equipment specifications
  • Application specific design to ensure a perfect fit
  • Engineered for the sealing repair environment
  • Validated for fit, form and function
  • Unsurpassed quality you can trust
See More

Yukon Gear – GM 10.5′ 14 Bolt Truck Cover Gasket (Part No.23016)

GM 10.5' 14 Bolt Truck Cover Gasket

from

$13.99
14T cover gasket.

Product Features:
  • Cover gasket
  • Fits GM 10.5″ 14 bolt truck
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Pro-King – Differential Cover Gasket (Part No.743B303)

Differential Cover Gasket

from

$3.99
Pro-King is the leading supplier of transmission and driveline products in the aftermarket.

Product Features:
  • All products are designed to meet or exceed OE quality, form, fit and funtion.
See More

Top Picks for 1978 GMC C25 Differential Pinion Seals

Invest in one of our 3 durable Differential Pinion Seals for your 1978 GMC, knowing you’re getting trusted brands and expert craftsmanship.

Yukon Gear – Pinion Seal For GM 14T (Part No.30023)

Pinion Seal For GM 14T

from

$19.99
Pinion seal for GM 14T.Yukon Mighty seal.

Product Features:
  • Pinion seal
  • Fits 1998 and down GM 10.5″ 14 bolt truck
See More

FAG US – Shaft Seal (Part No.SS3147)

Shaft Seal

from

$32.49
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
See More

FAG US – Shaft Seal (Part No.SS2776)

Shaft Seal

from

$19.79
Our wheel seals are engineered using only the highest-quality materials to meet vehicle manufacturer specificatons. We work with suppliers to design seals that meet FAG’s quality standards. Seals are designed to protect wheel end components from contamination – such as dirt, dust, and moisture – and prevent the loss of grease over the life of the bearing. The specifications for wheel seals are very demanding, and the type required depends on the specific application, position and vehicle class.

Product Features:
  • High-precision and High-quality components used in all KITs
  • Coverage of classic and new high-tech solutions for the best system coverage
See More

Top-Rated Differential Oil for 1978 GMC C25s

Make a smart move for your 1978 GMC C25 with products all priced from $11.99 to $148.99.

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

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

from

$14.49
Valvoline DEXRON-VI/MERCON LV ATF is a full-synthetic transmission fluid formulated with advanced additive technology to meet and exceed the requirements of the General Motors DEXRON-VI specification. It is officially licensed and approved by GM and is fully back-serviceable and can be used wherever DEXRON-II and/or DEXRON-III are recommended. Recommended for use in the following applications: DEXRON-VI, DEXRON-III, DEXRON-II, and Allison C-4.

Product Features:
  • Formulated with full-synthetic base stocks and advanced additive technology to meet the challenging demands of automatic transmissions
  • Enhanced anti-shudder protection for smooth shifting and maximum power transfer
  • Developed with anti-wear technology to help improve transmission durability
  • Engineered with a proprietary blend of base oils and advanced additives to provide better oil flow at low temperatures and greater film protection at higher temperatures
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Valvoline – DEX/MERC ATF Conventional Automatic Transmission Fluid, 1 Quart (Part No.798153)

DEX/MERC ATF Conventional Automatic Transmission Fluid, 1 Quart

from

$11.99
Valvoline DEX/MERC ATF is a high-quality transmission fluid formulated to meet the challenging demands of many automatic transmissions. Its responsive low-temperature fluidity is beneficial in both electronic and hydraulic controlled transmissions and transaxles. Recommended for use in the following applications: MERCON*, DEXRON*-III, Ford M2C138-CJ and M2C166-H, Allison C-4 and TES-389, and Caterpillar TO-2.

Product Features:
  • Formulated with premium base stocks and advanced additive technology to meet the challenging demands of automatic transmissions
  • Enhanced anti-shudder protection for smooth shifting and maximum power transfer
  • Developed with anti-wear technology to help improve transmission durability
  • Engineered with a proprietary blend of base oils and advanced additives to provide better oil flow at low temperatures and greater film protection at higher temperatures
See More

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
See More

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
See More

Top-Rated Differential Brands For Your 1978 GMC C25

When it comes to finding the perfect Differential for your 1978 GMC C25, Advance Auto Parts has you covered with a wide selection of high-quality OEM and aftermarket options from 14 trusted brands. We carry the most popular Differential brands including Valvoline, Richmond Gear, and National, and more, all known for their exceptional customer ratings (average brand rating of 4.8 stars) and competitive prices, as low as $10.99. Purchasing a Differential from us here at Advance Auto Parts is a smart move for both you and your 1978 GMC C25, providing peace of mind with parts that meet or exceed OEM standards.

Popular Valvoline 1978 GMC C25 Differentials

If you’re looking for a top-quality Differential for your 1978 GMC C25, Advance Auto Parts has exactly what you need with our selection of Valvoline Differentials. We have 1 Valvoline Differentials in stock for this fitment, all known for their durability and precision fit. With prices starting at just $14.49, you’ll find the perfect Differential for your needs and budget. Valvoline Differentials for the 1978 GMC C25 come highly rated, with over 2 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.
DEXRON - VI ATF Full Synthetic Automatic Transmission Fluid, 1 Quart
from $14.49
(2)
DEXRON – VI ATF Full Synthetic Automatic Transmission Fluid, 1 Quart
“I’ve used this in my 2005 2500HD since I bought the truck with 20k on it now at 280k changed every other year maybe 40k I’d put on in two years, I pu”

Top-Quality Richmond Gear 1978 GMC C25 Differentials

For those in search of a high-quality Differential for their 1978 GMC C25, Advance Auto Parts offers a great selection of Richmond Gear Differentials. With 1 Richmond Gear 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 $350.99, giving you a range of options to suit your budget. Backed by over 2 customer ratings and an average rating of 4.5 stars, Richmond Gear Differentials provide both reliability and excellent performance. Choosing a Richmond Gear Differential from Advance Auto Parts is a smart investment in your vehicle’s performance and longevity.
Differential Ring And Pinion
from $350.99
(2)
Differential Ring And Pinion
“I have a Chevy Impala 07 that runs on 3 cylinders when not needing the power of 6, and the new plugs have significantly provided an inexpensive tuneup”

FAQs for 1978 GMC C25 Differentials

What are the best-selling Differentials for 1978 GMC C25s?

Out of 138 Differentials that fit 1978 GMC C25s, the following parts are the top sellers:

What’s the price range for 1978 GMC C25 Differentials?

The prices of Differentials for the 1978 GMC C25 range from $0.91 up to $1,141.99 for the most premium parts.

What is the average price of a Differential for a 1978 GMC C25?

The average price for Differentials for the 1978 GMC C25 is $213.86. 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 GMC C25 model years?

Yes, we carry Differentials for 2 model years of GMC C25s between 1975 and 1977. The following model years are the most popular for Differential purchases: 1977, 1976, and 1975.

What are the cheapest Differentials for my 1978 GMC C25?

The cheapest 1978 GMC C25 Differentials we carry are:

Does Advance Auto Parts sell Differentials for any other 1978 GMC models?

Yes. We stock Differentials for 12 other popular 1978 GMC models. Some of the most popular are 1978 Jimmy Differentials, 1978 Caballero Differentials, 1978 K25 Differentials, 1978 K15 Differentials, and 1978 G25 Differentials.

What types of Differentials do you sell for my 1978 GMC C25?

As of 11/2/25, these are some of the most in-demand types of Differentials for a 1978 GMC C25:

Can I get help with 1978 GMC C25 Differential orders?

Contact our customer support team by chat or phone, through the help desk page, where you can find instant answers about GMC Differentials and more.

What is your return policy for GMC C25 Differentials?

Advance Auto Parts keeps returns simple. For new GMC C25 Differentials and accessories, your online orders can be returned, in their original condition, within 45 days. For requirements, see the returns page.