1978 GMC G15 Differentials

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Keep Your 1978 GMC G15 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 G15 looking sharp and performing at its best. At Advance Auto Parts we carry a wide selection of dependable options, including Differential Oil, 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 Richmond Gear, National, and Motive Gear. For example, Richmond Gear Differentials start at just $350.99 with an average 4.5 star rating. National and Motive Gear offer similar pricing and quality, backed by strong customer feedback. With over 5,604 reviews and a solid 4 star average, you can shop with confidence knowing other GMC G15 owners approve.

Competitive Prices and Extensive Inventory

The average price for a 1978 GMC G15 Differential at Advance Auto Parts is around $228.36, with a range that starts at $2.59 and goes up to $1,969.99. With 187 options in stock from 13 trusted brands, finding the right fit is easy. Popular picks like Axle Housing Cover Gasket Oval Shaped 10 Bolt Hole Gasket, 3 Qt – 80W90 Conventional Gear Oil With Posi Additive, 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 G15 in peak condition, inside and out.

Essential 1978 GMC G15 Differentials

Mr. Gasket – Differential Cover Kit (Part No.9895)

Differential Cover Kit

from

$85.99
The Mr. Gasket chrome plated rear end cover is made from heavy-gauge steel, and comes complete with bolts and gaskets.

Product Features:
  • Chrome plated steel for looks
  • Includes bolts and gasket
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Pro-King – Differential Cross Shaft (Part No.742G673)

Differential Cross Shaft

from

$28.49
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 – Dura Grip Positraction For GM 12 Bolt Truck With 30 Spline Axles, 3.73 & Up (Part No.26035)

Dura Grip Positraction For GM 12 Bolt Truck With 30 Spline Axles, 3.73 & Up

from

$859.99
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 GM 12 bolt truck with 30 spline axles
  • 3.73 and up ratio only
  • 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 – Standard Open Side Gear And Thrust Washer For GM 12 Bolt Car And Truck (Part No.33380)

Standard Open Side Gear And Thrust Washer For GM 12 Bolt Car And Truck

from

$7.99
Standard Open side gear thrust washer for 12P and 12T GM.

Product Features:
  • Side gear thust washer for GM 12 bolt passenger car and truck
  • Fits standard open differentials only
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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 – GM 12 Bolt Truck Cover Gasket (Part No.23015)

GM 12 Bolt Truck Cover Gasket

from

$12.99
12T cover gasket.

Product Features:
  • Cover gasket
  • Fits GM 12 bolt truck
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Yukon Gear – Minor Install Kit For GM 12 Bolt Truck Differential (Part No.12044)

Minor Install Kit For GM 12 Bolt Truck Differential

from

$151.99
Yukon Minimum installation kits are a low cost solution for gear changes in newer vehicles where the bearings can be reused. This kit uses all high quality components to ensure a smooth set up. kit includes a pinion seal, crush sleeve (if applicable), complete shim kit, marking compound and brush. (Includes Supershims).

Product Features:
  • Fits GM 12 bolt truck
  • Included are a pinion seal, crush sleeve, complete shim kit, marking compound and brush.
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Richmond Gear – MiniSpool (Part No.78-1230-1)

MiniSpool

from

$151.99
MiniSpool

Yukon Gear – 12P, 12T, CI Vet, & 55GM 8460N Redi Sleeve Yoke Saver (Part No.30225)

12P, 12T, CI Vet, & 55GM 8460N Redi Sleeve Yoke Saver

from

$109.99
12P, 12T, CI VET, & 55GM 8460N REDI sleeve yoke saver.Yukon Mighty seal.

Product Features:
  • Pinion Redi-sleeve
  • Fits GM 12 bolt passenger car, 12 bolt truck and 1963-1979 Corvette
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Yukon Gear – Pinion Install Kit For GM 12 Bolt Truck Differential (Part No.13057)

Pinion Install Kit For GM 12 Bolt Truck Differential

from

$232.99
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, pinion nut, 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 GM 12 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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Driveworks – Tapered Roller Bearing (Part No.S-HM-89449)

Tapered Roller Bearing

from

$17.29
Product Features:
  • Brand may vary by location
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USA Standard Gear – Axle Shaft For 2WD 12 Bolt Truck & 8.5" Van Rear (Part No.35055)

Axle Shaft For 2WD 12 Bolt Truck & 8.5" Van Rear

from

$188.99
USA Standard axle shaft for 2WD 12 bolt truck & 8.5″ van rear. 33 3/8″ long, 30 spline, 5 lug.

Product Features:
  • Fits GM 12 bolt truck with 2 wheel drive and van
  • 30 spline
  • 33 3/8″ long
  • 5 lug
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Driveworks – Oil Seal (Part No.S-2043)

Oil Seal

from

$10.79
Value-priced seal meets all cataloged application requirements.

Product Features:
  • Brand may vary by location
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Dorman – Differential Ring and Pinion Set (Part No.697-301)

Differential Ring and Pinion Set

from

$316.99
This differential ring and pinion directly replaces the original equipment on specific vehicle years, makes and models.

Product Features:
  • Direct replacement – this ring and pinion set matches the fit and function of the original components on certain vehicle applications
  • Effective fix – eliminates grinding and whining from failed original bearings
  • Thoroughly tested – vehicle try-on testing and rigorous quality control measures ensure longevity
  • Trustworthy quality – backed by team of designers and engineers in the United States
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Yukon Gear – Crush Sleeve Eliminator Kit For GM 12 Bolt Truck (Part No.55046)

Crush Sleeve Eliminator Kit For GM 12 Bolt Truck

from

$47.99
12T solid crush sleeve replacement spacer, pinion preload.

Product Features:
  • Crush sleeve eliminator kit for GM 12 bolt truck
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Yukon Gear – Ring Gear Bolt (Part No.33046)

Ring Gear Bolt

from

$6.99
Ring gear bolt for GM 12 bolt car & truck, 8.2″, 8.2″ for Buick/Olds/Pontiac, 63-79 Corvette & 55-62 GM Car & Truck. 3/8″ x 24.

Product Features:
  • Ring gear bolt for GM 12 bolt passenger car and truck, 1955-1964 passenger car and truck, GM 8.2″, 8.2″ Buick, Oldsmobile and Pontiac and 1963-1979 Corvette
  • 3/8″ x 24 thread
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Yukon Gear – Standard Open Spider Gear Kit For GM 12 Bolt Car And Truck With 30 Spline Axles (Part No.16043)

Standard Open Spider Gear Kit For GM 12 Bolt Car And Truck With 30 Spline Axles

from

$207.99
Yukon standard open spider gear kit for GM 12P and 12T 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 12 bolt passenger car and truck open differential with 30 spline axles
  • Includes two side gears, two pinion gears, cross pin shaft, cross pin bolt and spider gear thrust washers.
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Yukon Gear – 3/8" Ring Gear Bolt Washer For GM 12 Bolt Car & Truck, 8.2 Bop & More (Part No.33347)

3/8" Ring Gear Bolt Washer For GM 12 Bolt Car & Truck, 8.2 Bop & More

from

$4.99
3/8″ ring gear bolt washer for GM 12 bolt car & truck, 8.2 BOP & more.

Product Features:
  • Ring gear bolt washer for GM 12 bolt car and truck, 1955-1964 passenger car, 1963-1979 Corvette and 8.2″ Buick, Oldsmobile and Pontiac
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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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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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Dorman – Premium Ring and Pinion Master Bearing and Installation Kit (Part No.797-100)

Premium Ring and Pinion Master Bearing and Installation Kit

from

$243.99
If you’re repairing or rebuilding a front or rear differential and want the best performance and longevity from the bearings being replaced, choose this premium differential kit. It includes high-precision bearings manufactured to tighter tolerances and engineered to last longer than common lower-grade bearings that have more backlash when subjected to the torque generated within the differential. This convenient kit also saves the time needed to source individual components. Check the product attributes and fitment details to select the correct premium differential kit for your application.

Product Features:
  • Ideal solution – this premium differential bearing kit features high-precision bearings to help ensure longer bearing life, prevent backlash, and restore proper differential operation
  • Direct replacement – the components in this all-in-one kit are engineered to precisely match the fit and function of the original equipment bearings for a seamless installation
  • Increased reliability – the premium bearings in this kit are manufactured to exacting tolerances and specifications from high quality materials to help ensure optimal performance
  • Application-specific – check the product attributes and fitment details to choose the correct kit for your application
  • Contents: Bearings; Shims; Crush Collar; Hardware; Gasket Material; Gear Marking Compound; Application Brush; Thread Lock Compound
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Yukon Gear – 18 Plate Steel Clutches For GM 8.2", GM 8.5", 12T, 12P, Ford 8.8" & Cast Iron ‘Vette (Part No.16110)

18 Plate Steel Clutches For GM 8.2", GM 8.5", 12T, 12P, Ford 8.8" & Cast Iron 'Vette

from

$483.99
Product Features:
  • Clutch kit
  • Fits Ford 8.8″, 1963-1979 Corvette, GM 12 bolt passenger car and truck, 8.2″, 8.5″ and 8.6″ Dura Grip positraction
  • 18 piece kit
  • Steel clutches
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Pro-King – Differential Pinion Gear Washer (Part No.742G216)

Differential Pinion Gear Washer

from

$2.59
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 – Bearing Race Driver (Part No.56017)

Bearing Race Driver

from

$215.99
Bearing race driver. No return.

Product Features:
  • Bearing race driver
  • Fits HM89410 race
  • All steel construction
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Powertrax – Lock Right Locker (Part No.1921-LR)

Lock Right Locker

from

$368.99
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!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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    Felpro – Axle Housing Cover Gasket Oval Shaped 10 Bolt Hole Gasket (Part No.RDS 55028-1)

    Axle Housing Cover Gasket Oval Shaped 10 Bolt Hole Gasket

    from

    $10.99
    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
    • Unsurpassed quality you can trust
    • Validated for fit, form and function
    • Each Fel-Pro gasket, no matter how small, is engineered to exacting standards with proprietary design, engineering and manufacturing processes
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    Pro-King – Differential Cover Plug (Part No.742G484)

    Differential Cover Plug

    from

    $6.99
    Pro-King is the leading supplier of transmission and driveline products in the aftermarket.

    Product Features:
    • Meets or exceeds OE specifications
    See More

    Most Popular Differential Oil for 1978 GMC G15s

    Enhance your 1978 GMC G15 with one of the 7 Differential Oil we have in stock, starting at just $12.99.

    Valvoline – MaxLife Multi-Vehicle Automatic Transmission Fluid, 1 Gallon (Part No.773775)

    MaxLife Multi-Vehicle Automatic Transmission Fluid, 1 Gallon

    from

    $35.99
    Valvoline MaxLife Multi-Vehicle ATF is a full-synthetic formulation with advanced additives to prevent the major causes of transmission breakdown and help extend transmission life.  Developed to help prevent leaks, maximize transmission performance, reduce transmission wear, and maintain smooth shifting longer than conventional fluids. It is suitable for use in a broad range of ATF applications including most Ford, GM, Toyota, Honda, Nissan, Hyundai, BMW, Mercedes, Volvo, VW & Audi. Recommended for use in the following applications: GM DEXRON-II, DEXRON-III, DEXRON-VI, Ford MERCON LV, Toyota/Lexus Type T, T-II, T-IV, WS, Honda/Acura, ATF-Z1, Nissan/Infiniti Matic-D, Matic-J, Matric-K, Matic-S, Hyundai/Kia SP-II, SP-III, SP-IV, SPH-IV, BMW 7045E, ETL 8072B, LA2634, LT71141, Allison C-4, Mercedes Benz NAG-1, Volvo 1161521, 1161540, 97340, 1273.41, and VW/Audi G-052-025-A2, G-052-162-A1. For CVT applications Valvoline recommends Valvoline Full Synthetic CVT Fluid.

    Product Features:
    • Formulated with full-synthetic base oils and long life friction modifiers to help improve smooth shifting, eliminate slippage and shudder, prevent clutch wear and improve drivability longer than conventional fluids
    • High-performance seal conditioners maintain and preserve the elasticity of seals to help prevent leaks in high mileage transmissions
    • 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 – High Performance Transmission & Differential Gear Oil: Conventional 80W-90, 1 Quart (Part No.VV831)

    High Performance Transmission & Differential Gear Oil: Conventional 80W-90, 1 Quart

    from

    $12.99
    Valvoline High Performance Gear Oil is an extreme pressure gear lubricant formulated with quality base oils and superior additives that helps protect against severe temperatures, shock loads, scuffing, scouring, corrosion and pitting in high speed, high load, high torque and high horsepower conditions.

    Product Features:
    • Formulated for reliable gear protection
    • Protects against severe temperatures to help extend service life
    • Formulated with extreme-pressure additives to minimize gear wear from shock loads
    • Helps protect against gear wear from scuffing, scouring, corrosion and pitting
    • Recommended for conventional hypoid differentials and non-synchronized manual transmissions in passenger cars, light trucks, sport utility vehicles, vans and heavy-duty trucks where an API-GL5 or GL-4 fluid is specified
    • PLEASE NOTE: Valvoline recommends SynPower Full Synthetic Gear Oil for limited slip differentials
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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
    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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    Best-Selling 1978 GMC G15 Differential Covers

    Upgrade your G15 with one of our 4 best-selling Differential Covers, earning an average 1.5 stars rating across 2 reviews.

    Mr. Gasket – Differential Cover Kit (Part No.9895)

    Differential Cover Kit

    from

    $85.99
    The Mr. Gasket chrome plated rear end cover is made from heavy-gauge steel, and comes complete with bolts and gaskets.

    Product Features:
    • Chrome plated steel for looks
    • Includes bolts and gasket
    See More

    Yukon Gear – Chrome Cover For GM 12 Bolt Truck (Part No.32012)

    Chrome Cover For GM 12 Bolt Truck

    from

    $64.99
    Chrome cover for GM 12T.

    Product Features:
    • Fits GM 12 bolt truck
    • Chrome
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    Yukon Gear – Polished Aluminum Cover For GM 12 Bolt Truck (Part No.32027)

    Polished Aluminum Cover For GM 12 Bolt Truck

    from

    $269.99
    Polished aluminum cover for 12T GM.

    Product Features:
    • Fits GM 12 bolt truck
    • Finned polished aluminum
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    Pro-King – Differential Carrier Cover (Part No.742G758A)

    Differential Carrier Cover

    from

    $21.99
    Pro-King High Quality Differential Products are designed for trouble free installation and setup.

    Product Features:
    • Meets or exceeds OE specifications
    See More

    Top-Quality Rear Housing Cover Gaskets for 1978 GMC G15s

    Choose a high-quality OEM or aftermarket Rear Housing Cover Gasket for GMC G15s and enjoy top-notch performance from $10.99.

    Felpro – Axle Housing Cover Gasket Oval Shaped 10 Bolt Hole Gasket (Part No.RDS 55028-1)

    Axle Housing Cover Gasket Oval Shaped 10 Bolt Hole Gasket

    from

    $10.99
    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
    • Unsurpassed quality you can trust
    • Validated for fit, form and function
    • Each Fel-Pro gasket, no matter how small, is engineered to exacting standards with proprietary design, engineering and manufacturing processes
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    Top Picks for 1978 GMC G15 Differential Bearings

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

    Driveworks – Taper Bearing Cone (Part No.S-LM-501349)

    Taper Bearing Cone

    from

    $10.99
    Value-priced bearing meets all cataloged application requirements.

    Product Features:
    • Brand may vary by location
    See More

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

    Multi-Purpose Bearing

    from

    $27.99
    Product Features:
    • CONSISTENT PERFORMANCE: Matched cup and cone components ensure consistent performance
    • PREMIUM MATERIALS: Precision manufactured using premium-grade steel for outstanding durability and performance
    • SMOOTH ROTATION: Crowned raceways and rollers for even load distribution
    • OE-STYLE DESIGN: Engineered to meet OE specifications
    • COMPREHENSIVE COVERAGE: Industry-leading coverage for domestic and import applications
    • RIGOROUS TESTING: Comprehensive testing throughout design and development processes by National engineers for quality you can count on
    See More

    Schaeffler – Bearing – TRB (Tapered Roller Bearing) (Part No.KT36)

    Bearing - TRB (Tapered Roller Bearing)

    from

    $34.49
    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-Rated Rear Differential Cover Gaskets for 1978 GMC G15s

    Make a smart move for your 1978 GMC G15 with products all priced from $9.49 to $31.49.

    Felpro – Axle Housing Cover Gasket Irregular Shaped 12 Bolt Hole Gasket (Part No.RDS 13391)

    Axle Housing Cover Gasket Irregular Shaped 12 Bolt Hole Gasket

    from

    $9.49
    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

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

    Differential Gasket

    from

    $21.49
    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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    Pro-King – Differential Cover Gasket (Part No.742G303A)

    Differential Cover Gasket

    from

    $31.49
    Pro-King is the leading supplier of transmission and driveline products in the aftermarket.

    Product Features:
    • Meets or exceeds OE specifications
    See More

    Yukon Gear – GM 12 Bolt Truck Cover Gasket (Part No.23015)

    GM 12 Bolt Truck Cover Gasket

    from

    $12.99
    12T cover gasket.

    Product Features:
    • Cover gasket
    • Fits GM 12 bolt truck
    See More

    Top-Rated Differential Brands For Your 1978 GMC G15

    When it comes to finding the perfect Differential for your 1978 GMC G15, Advance Auto Parts has you covered with a wide selection of high-quality OEM and aftermarket options from 13 trusted brands. We carry the most popular Differential brands including Richmond Gear, National, and Motive Gear, and more, all known for their exceptional customer ratings (average brand rating of 4.5 stars) and competitive prices, as low as $11.99. Purchasing a Differential from us here at Advance Auto Parts is a smart move for both you and your 1978 GMC G15, providing peace of mind with parts that meet or exceed OEM standards.

    Popular Richmond Gear 1978 GMC G15 Differentials

    If you’re looking for a top-quality Differential for your 1978 GMC G15, Advance Auto Parts has exactly what you need with our selection of Richmond Gear Differentials. We have 3 Richmond Gear Differentials in stock for this fitment, all known for their durability and precision fit. With prices starting at just $350.99 and an average cost of $354.32, you’ll find the perfect Differential for your needs and budget. Richmond Gear Differentials for the 1978 GMC G15 come highly rated, with over 10 customer reviews and an impressive average rating of 4.5 stars. Choosing a Richmond Gear Differential from Advance Auto Parts is a smart move to ensure quality and value for your vehicle.
    Differential Ring And Pinion
    from $350.99
    (7)
    Differential Ring And Pinion
    “Great spark plugs.”
    Differential Ring And Pinion
    from $360.99
    (1)
    Differential Ring And Pinion
    “Best ever!!!’nn”
    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”

    Top-Quality National 1978 GMC G15 Differentials

    For those in search of a high-quality Differential for their 1978 GMC G15, 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 $24.66, giving you a range of options to suit your budget. Backed by over 9 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.
    Bearing Race
    from $11.99
    (2)
    Bearing Race
    “Reasonable price and woks well. front diff 2006 Escalade esv”
    Shaft Repair Sleeve
    from $43.99
    (2)
    Shaft Repair Sleeve
    “As a mechanic I dont have time or money to waste on inferior products, which this is not. Great product,great price”
    Differential Pinion Seal
    from $17.99
    (5)
    Differential Pinion Seal
    “Perfect fit”

    FAQs for 1978 GMC G15 Differentials

    What are the best-selling Differentials for 1978 GMC G15s?

    Out of 187 Differentials that fit 1978 GMC G15s, the following parts are the top sellers:

    What’s the price range for 1978 GMC G15 Differentials?

    The prices of Differentials for the 1978 GMC G15 range from $2.59 up to $1,969.99 for the most premium parts.

    What is the average price of a Differential for a 1978 GMC G15?

    The average price for Differentials for the 1978 GMC G15 is $228.36. 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 G15 model years?

    Yes, we carry Differentials for 2 model years of GMC G15s 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 G15?

    The cheapest 1978 GMC G15 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 G15?

    As of 3/1/26, these are some of the most in-demand types of Differentials for a 1978 GMC G15:

    Can I get help with 1978 GMC G15 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 G15 Differentials?

    Advance Auto Parts keeps returns simple. For new GMC G15 Differentials and accessories, your online orders can be returned, in their original condition, within 45 days. For requirements, see the returns page.