1988 GMC S15 Differentials

Keep Your 1988 GMC S15 in Top Shape with Quality Differentials

Whether you’re repairing or upgrading your Differential, using high-quality parts is key to keeping your 1988 GMC S15 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 Differential Pinion Seals. 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 National, Dorman, and Valvoline. For example, National Differentials start at just $7.99 with an average 4.3 star rating. Dorman and Valvoline offer similar pricing and quality, backed by strong customer feedback. With over 462 reviews and a solid 4 star average, you can shop with confidence knowing other GMC S15 owners approve.

Competitive Prices and Extensive Inventory

The average price for a 1988 GMC S15 Differential at Advance Auto Parts is around $318.92, with a range that starts at $2.49 and goes up to $2,219.99. With 211 options in stock from 15 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 4WD Components and Universal Joints. At Advance Auto Parts, we’re here to help you keep your 1988 GMC S15 in peak condition, inside and out.

Essential 1988 GMC S15 Differentials

Pro-King – Crush Sleeve (Part No.741A034)

Crush Sleeve

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.
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Yukon Gear – Bearing Race Driver (Part No.56023)

Bearing Race Driver

from

$219.99
Bearing race driver. No return.

Product Features:
  • Bearing race driver
  • Fits M88010 race
  • All steel construction
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MOOG – Differential Carrier Bushing (Part No.K6572)

Differential Carrier Bushing

from

$18.29
By constantly introducing design enhancements that extend product life and simplify installation and replacement, MOOG has earned its reputation as the chassis industry’s Problem Solver.

Product Features:
  • Manufactured from high quality elastomer compounds for durability and ride performance
  • Assembled with proper precompression for ultimate in performance and feel
  • High level bonding adhesive is used for durability
  • Elastomer compounds do not utilize any reground rubber fillers
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Richmond Gear – Differential Cross Shaft (Part No.CSPGM75)

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 – Posi Spring Kit For GM 7.5", With Preload Plates (Part No.33206)

Posi Spring Kit For GM 7.5", With Preload Plates

from

$153.99
Product Features:
  • Positraction spring kit
  • Fits GM 7.5″ and 7.625″ Dura Grip
  • Includes preload plates
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Yukon Gear – Standard Open Spider Gear Kit For Early 7.5" GM With 26 Spline Axles And Large Windows (Part No.16048)

Standard Open Spider Gear Kit For Early 7.5" GM With 26 Spline Axles And Large Windows

from

$149.99
Yukon standard open spider gear kit for early 7.5″ GM with 26 spline axles and large windows. 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 7.5″ open differential with 26 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 – 14 Plate Dura Grip Composite Clutches, GM 7.5 (Part No.16119)

14 Plate Dura Grip Composite Clutches, GM 7.5

from

$202.99
14 plate DURAGRIP COMPOSITE clutches, GM 7.5.

Product Features:
  • Clutch kit
  • Fits GM 7.5″ and 7.625″ with Dura Grip positraction
  • Steel clutches
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Pro-King – Differential Cross Shaft (Part No.742G930)

Differential Cross Shaft

from

$2.99
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

Powertrax – No-Slip Traction System (Part No.9207853005)

No-Slip Traction System

from

$544.99
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!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!
  • See More

    Yukon Gear – Posi Shim Kit For GM 7.5" & 7.625" Eaton Positraction (Part No.16047)

    Posi Shim Kit For GM 7.5" & 7.625" Eaton Positraction

    from

    $42.99
    Product Features:
    • Shim kit
    • Fits GM 7.5″ and 7.625″ with Eaton positraction
    See More

    Yukon Gear – Super Carrier Shim Kit For Ford 7.5", GM 7.5", 8.2" & 8.5" (Part No.55001)

    Super Carrier Shim Kit For Ford 7.5", GM 7.5", 8.2" & 8.5"

    from

    $59.99
    Product Features:
    • Super carrier shim kit for Ford 7.5″, GM 7.5″, 7.625″, 7.6″ IFS, 7.6″ IRS, 7.75″, 8.2″, 8.2″ Buick, Oldsmobile and Pontiac and GM 8.5″ front and rear
    • Interlocking design makes installation much easier
    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

    ATP – DIFF COVER KIT (Part No.111102)

    DIFF COVER KIT

    from

    $29.99
    DIFF COVER KIT

    Motive Gear – Pinion Nut (Part No.1260823)

    Pinion Nut

    from

    $8.49
    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.
    See More

    Yukon Gear – Pinion Depth Shim Kit For Toyota8", GM 7.5", 8.2" & 12 Bolt Truck (Part No.55064)

    Pinion Depth Shim Kit For Toyota8", GM 7.5", 8.2" & 12 Bolt Truck

    from

    $39.99
    8″ Toyota, 7.5″ GM, 8.2″ GM, 12T, pinion shim set, & Mazda truck.

    Product Features:
    • Pinion depth shim kit for Toyota 7.5″, 8″ and V6
    See More

    Pro-King – Differential Internal Nest Kit (Part No.741A717A)

    Differential Internal Nest Kit

    from

    $155.99
    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

    Richmond Gear – RngPnnInstlKt (Part No.83-1044-B)

    RngPnnInstlKt

    from

    $43.99
    RngPnnInstlKt

    Yukon Gear – 7.5 GM Cover Gasket (Part No.23018)

    7.5 GM Cover Gasket

    from

    $11.99
    7.5 GM cover gasket.

    Product Features:
    • Cover gasket
    • Fits GM 7.5″ and 7.625″
    See More

    Yukon Gear – Mini Spool For GM 7.6" With 28 Spline Axles (Part No.32229)

    Mini Spool For GM 7.6" With 28 Spline Axles

    from

    $194.99
    Mini spools are a low-cost traction option for vehicles looking for full-time lockup. The mini spool installs into a standard open carrier and give 100% power to both tires at all times. These units are not recommended for street-driven vehicles. We recommend full spools for vehicles with large tires or high horsepower. These units come with a one year warranty against manufacturing defects.

    Product Features:
    • Fits 2000 and up GM 7.5″ and 7.625″
    • 28 spline
    See More

    National – Multi-Purpose Seal (Part No.710532)

    Multi-Purpose Seal

    from

    $17.99
    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; single-lip
    • Temperature range: -20 Deg. F to 300 Deg. F / -29 Deg. C to 49 Deg. C
    • Resistance to EP lubricants
    • Low swell in hydrocarbon fluids
    • Delivers quality and reliable performance for every type of repair
    See More

    Yukon Gear – 7.2" Shifter Seal (Part No.30280)

    7.2" Shifter Seal

    from

    $28.99
    7.2″ shifter seal.Yukon Mighty seal.

    Product Features:
    • Shifter seal
    • Fits GM 7.2″ IFS
    See More

    Powertrax – Grip LS Traction System (Part No.LS201028)

    Grip LS Traction System

    from

    $463.99
    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 – Adapter Sleeve Fro GM 7.2", 7.625" & 8.0" Yokes To Use Triple Lip Pinion Seal (Part No.41210)

    Adapter Sleeve Fro GM 7.2", 7.625" & 8.0" Yokes To Use Triple Lip Pinion Seal

    from

    $25.99
    Yukon 4340 Chrome-Moly replacement outer stub for D44 ’87-’94 Wrangler with a length of 8.31″ and 27 splines. Yukon 4340 Chrome-Moly axles provide up to 50% increased strength over stock axles for use in extreme performance applications with large tires and high horsepower. Yukon’s 4340 axles are manufactured using the latest technologies and the highest quality materials to ensure high strength and long life. Limited Lifetime warranty covers manufacturing defects and axle breakage for as long as you own the vehicle. This warranty is not transferable to another party. “No Questions Asked” replacement for first warranty return, however Yukon reserves the right to either replace axle or refund original purchase price after the first warranty claim. Yukon (through Randy’s ring & pinion) makes final determination on warranty considerations.

    Product Features:
    • 27 spline
    • 8.31″ long
    • Fits Dana Spicer 30 in 1987-1994 Wrangler
    • Outer stub
    • 5-760X U-joint size
    • 4340 Chromoly
    • For WARN hub conversion only
    See More

    Yukon Gear – Minor Install Kit For GM ’83-’97 7.2" IFS Differential (Part No.12048)

    Minor Install Kit For GM '83-'97 7.2" IFS Differential

    from

    $40.99
    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.

    Product Features:
    • Fits GM 7.2″ IFS
    • Included are a pinion seal, crush sleeve, complete shim kit, marking compound and brush.
    See More

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

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

    from

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

    Product Features:
    • Cover bolt for Dana Spicer 25, 27, 30 and 44, AMC Model 20 and Model 35, GM 7.5″, 7.625″, 8.2″, 8.5″ and 12 bolt passenger car and truck.
    • 1/2″ head
    See More

    Yukon Gear – Standard Open Pinion Gear And Thrust Washer For 7.2" GM (Part No.33376)

    Standard Open Pinion Gear And Thrust Washer For 7.2" GM

    from

    $7.99
    Standard open pinion gear thrust washer for 7.2″ GM.

    Product Features:
    • Pinion gear thrust washer
    • Fits GM 7.2″ IFS
    See More

    National – Tapered Roller Bearing Cone (Part No.HM89249)

    Tapered Roller Bearing Cone

    from

    $30.49
    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 – Axle Differential Bearing & Seal Kit (Part No.RA-320)

    Axle Differential Bearing & Seal Kit

    from

    $151.99
    The National bearing & seal kit includes all the components required to complete the repair.

    Product Features:
    • COMPLETE SOLUTION – Includes everything needed to complete the repair
    • STRONG AND DURABLE – Controlled heat treatment process for strength and durability
    • COMPREHENSIVE COVERAGE – Industry-leading coverage for domestic and import applications
    • RIGOROUS TESTING – Comprehensive testing throughout design and development processes by National engineers for quality you can count on
    • Professional technicians know they can depend on National
    See More

    Most Popular Differential Covers for 1988 GMC S15s

    Enhance your 1988 GMC S15 with one of the 7 Differential Covers we have in stock, starting at just $24.99.

    Dorman – Differential Cover (Part No.697-701)

    Differential Cover

    from

    $24.99
    This direct replacement differential cover matches the fit and function of the original equipment diff cover for a reliable, leak-free repair. It features a durable design, made to strict specifications, to help ensure reliable service life.

    Product Features:
    • Direct replacement – this differential cover matches the fit and function of the original equipment diff cover on select vehicles
    • Reliable repair – the smart solution for fixing an existing cover that’s rusted, damaged or leaking differential fluid
    • Durable construction – this differential cover is made according to strict engineering standards to help ensure dependability
    • Trustworthy quality – backed by a team of product experts in the United States and more than a century of automotive experience
    See More

    ATP – DIFF COVER KIT (Part No.111102)

    DIFF COVER KIT

    from

    $29.99
    DIFF COVER KIT

    Yukon Gear – Aluminum Girdle Cover For GM 7.5" & 7.625" (Part No.32118)

    Aluminum Girdle Cover For GM 7.5" & 7.625"

    from

    $379.99
    Product Features:
    • Fits GM 7.5″ and 7.625″
    • Aluminum girdle cover
    See More

    Yukon Gear – Steel Cover For GM 7.5" & 7.625" (Part No.32331)

    Steel Cover For GM 7.5" & 7.625"

    from

    $67.99
    Product Features:
    • Fits GM 7.5″ and 7.625″
    • Steel
    See More

    Yukon Gear – Chrome Cover For 7.5" GM (Part No.32014)

    Chrome Cover For 7.5" GM

    from

    $67.99
    Chrome cover for 7.5″ GM.

    Product Features:
    • Fits GM 7.5″ and 7.625″
    • Chrome
    See More

    ATP – DIFF COVER KIT (Part No.111101)

    DIFF COVER KIT

    from

    $35.99
    DIFF COVER KIT

    Pro-King – Differential Carrier Cover (Part No.741A758)

    Differential Carrier Cover

    from

    $29.99
    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

    Best-Selling 1988 GMC S15 Differential Bearings

    Upgrade your S15 with one of our 10 best-selling Differential Bearings, earning an average 4 stars rating across 4 reviews.

    National – Bearing Race (Part No.LM501314)

    Bearing Race

    from

    $9.29
    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

    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.LM67010)

    Bearing Race

    from

    $4.49
    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
    • 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

    FAG US – Cone (Part No.KM86649)

    Cone

    from

    $24.29
    With advanced load-carrying capacity and compact design, tapered roller bearings are used in wheel bearings, transmissions, differentials, transfer cases and other miscellanous applications. FAG manufacturers over 100 million tapered roller bearings annually.

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

    FAG US – Bearing – TRB (Tapered Roller Bearing) (Part No.KT11)

    Bearing - TRB (Tapered Roller Bearing)

    from

    $21.79
    With advanced load-carrying capacity and compact design, tapered roller bearings are used in wheel bearings, transmissions, differentials, transfer cases and other miscellanous applications. FAG manufacturers over 100 million tapered roller bearings annually.

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

    FAG US – Bearing – TRB (Tapered Roller Bearing) (Part No.KT5)

    Bearing - TRB (Tapered Roller Bearing)

    from

    $21.29
    With advanced load-carrying capacity and compact design, tapered roller bearings are used in wheel bearings, transmissions, differentials, transfer cases and other miscellanous applications. FAG manufacturers over 100 million tapered roller bearings annually.

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

    FAG US – Cup (Part No.M88010)

    Cup

    from

    $11.29
    With advanced load-carrying capacity and compact design, tapered roller bearings are used in wheel bearings, transmissions, differentials, transfer cases and other miscellanous applications. FAG manufacturers over 100 million tapered roller bearings annually.

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

    National – Bearing Race (Part No.JL69310)

    Bearing Race

    from

    $7.29
    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 – Cross Pin Bolt (Part No.33067)

    Cross Pin Bolt

    from

    $6.99
    Cross pin bolt for Chrysler 8.25″, 9.25″ rear, Ford 7.5″, 8.8″, GM 12 bolt car & truck, 7.2″ IFs, 7.5″, 7.6″, 8.0″, 8.25″ IFS & 8.5″.

    Product Features:
    • Cross pin bolt for Chrysler 8.25″ and 9.25″ rear, Ford 7.5″ and 8.8″, GM 12 botl car and truck, 8.5″, 8.25″ IFS, 8.0″, 7.625″, 7.5″ and 7.2″ IFS
    See More

    FAG US – Cup (Part No.LM67010)

    Cup

    from

    $6.69
    With advanced load-carrying capacity and compact design, tapered roller bearings are used in wheel bearings, transmissions, differentials, transfer cases and other miscellanous applications. FAG manufacturers over 100 million tapered roller bearings annually.

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

    Top-Quality Differential Pinion Seals for 1988 GMC S15s

    Choose a high-quality OEM or aftermarket Differential Pinion Seal for GMC S15s and enjoy top-notch performance from $4.99.

    National – Multi-Purpose Seal (Part No.710532)

    Multi-Purpose Seal

    from

    $17.99
    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; single-lip
    • Temperature range: -20 Deg. F to 300 Deg. F / -29 Deg. C to 49 Deg. C
    • Resistance to EP lubricants
    • Low swell in hydrocarbon fluids
    • Delivers quality and reliable performance for every type of repair
    See More

    Motive Gear – Pinion Seal (Part No.8610)

    Pinion Seal

    from

    $4.99
    Motive Gear offers some of the toughest drive train components on the market today. If you are looking for the largest line of performance ring and pinion gear options available with gear sets in a wide range of ratios for nearly every application, both on and off-road, check out Motive Gear. Motive Gear products can be found in the winner’s circle at racing events worldwide. The superior quality of Motive Gear components is the result of years of racing development, outstanding design and state-of-the-art manufacturing methods. Extensive testing is performed on all products by our in-house engineers.
    See More

    Yukon Gear – 7.2" GM 7.5" GM & 8.2" GM Pinion Seal (Part No.30192)

    7.2" GM 7.5" GM & 8.2" GM Pinion Seal

    from

    $9.99
    7.2″ GM 7.5″ GM & 8.2″ GM pinion seal.Yukon Mighty seal.

    Product Features:
    • Pinion seal
    • Fits GM 7.2″ IFS, 1999 and down GM 7.5″ and 7.625″ and GM 8.2″
    • 2.660″ O.D.
    See More

    Top Picks for 1988 GMC S15 Rear Differential Cover Gaskets

    Invest in one of our 2 durable Rear Differential Cover Gaskets for your 1988 GMC, knowing you’re getting trusted brands and expert craftsmanship.

    Felpro – Axle Housing Cover Gasket Irregular Shaped 10 Bolt Hole Gasket (Part No.RDS 55072)

    Axle Housing Cover Gasket Irregular Shaped 10 Bolt Hole Gasket

    from

    $8.99
    Fel-Pro® gaskets are specifically designed for the repair environment to deliver a reliable seal on even the most troublesome applications. Designed for imperfect sealing surfaces and manufactured with proprietary materials, you can count on Fel-Pro for innovative sealing solutions for the real-world repair environment.

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

    Yukon Gear – 7.5 GM Cover Gasket (Part No.23018)

    7.5 GM Cover Gasket

    from

    $11.99
    7.5 GM cover gasket.

    Product Features:
    • Cover gasket
    • Fits GM 7.5″ and 7.625″
    See More

    Top-Rated Differential Oil for 1988 GMC S15s

    Make a smart move for your 1988 GMC S15 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
    See More

    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
    See More

    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 1988 GMC S15

    When it comes to finding the perfect Differential for your 1988 GMC S15, Advance Auto Parts has you covered with a wide selection of high-quality OEM and aftermarket options from 15 trusted brands. We carry the most popular Differential brands including Valvoline, National, and Dorman, and more, all known for their exceptional customer ratings (average brand rating of 4.8 stars) and competitive prices, as low as $6.79. Purchasing a Differential from us here at Advance Auto Parts is a smart move for both you and your 1988 GMC S15, providing peace of mind with parts that meet or exceed OEM standards.

    Popular Valvoline 1988 GMC S15 Differentials

    If you’re looking for a top-quality Differential for your 1988 GMC S15, 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 1988 GMC S15 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 National 1988 GMC S15 Differentials

    For those in search of a high-quality Differential for their 1988 GMC S15, 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 $7.99, with an average price of $56.42, giving you a range of options to suit your budget. Backed by over 8 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 $9.29
    (2)
    Bearing Race
    “Reasonable price and woks well. front diff 2006 Escalade esv”
    Axle Differential Bearing & Seal Kit
    from $151.99
    (2)
    Axle Differential Bearing & Seal Kit
    “All you need to overhaul a diff, at a good price”
    Bearing Race
    from $7.99
    (4)
    Bearing Race
    “Goes with M88010 bearing cup. Application was the pinion bearing race for a Ford 9 Inch on a 1957 Ford F-100.”

    FAQs for 1988 GMC S15 Differentials

    What are the best-selling Differentials for 1988 GMC S15s?

    Out of 211 Differentials that fit 1988 GMC S15s, the following parts are the top sellers:

    What’s the price range for 1988 GMC S15 Differentials?

    The prices of Differentials for the 1988 GMC S15 range from $2.49 up to $2,219.99 for the most premium parts.

    What is the average price of a Differential for a 1988 GMC S15?

    The average price for Differentials for the 1988 GMC S15 is $318.92. 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 S15 model years?

    Yes, we carry Differentials for 7 model years of GMC S15s between 1982 and 1990. The following model years are the most popular for Differential purchases: 1990, 1989, 1987, 1986, 1985, 1984, 1983, and 1982.

    What are the cheapest Differentials for my 1988 GMC S15?

    The cheapest 1988 GMC S15 Differentials we carry are:

    Does Advance Auto Parts sell Differentials for any other 1988 GMC models?

    Yes. We stock Differentials for 24 other popular 1988 GMC models. Some of the most popular are 1988 Jimmy Differentials, 1988 K2500 Differentials, 1988 C2500 Differentials, 1988 K1500 Differentials, and 1988 C1500 Differentials.

    What types of Differentials do you sell for my 1988 GMC S15?

    As of 11/2/25, these are some of the most in-demand types of Differentials for a 1988 GMC S15:

    Can I get help with 1988 GMC S15 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 S15 Differentials?

    Advance Auto Parts keeps returns simple. For new GMC S15 Differentials and accessories, your online orders can be returned, in their original condition, within 45 days. For requirements, see the returns page.