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Looking for aftermarket parts to modify or upgrade your 1978 GMC K15 with differentials? At Tunersports.com we carry a huge selection of the top name brand performance differential parts and accessories.
 IN STOCK - LOW YDGD44-3-30-1The Yukon Dura Grip provides aggressive yet smooth traction to give you the confidence and performance you need. Get longer life and better traction with the heavy duty Yukon Dura Grip Positraction.... Yukon Gear Dura Grip For Dana 44 / 30 Spline / 3.73 & Down 1975-1978 GMC K15 Base / High Sierra / Sierra Classic / Sierra Grande $901.89 |
 IN STOCK YDGD44-4-30-1The Yukon Dura Grip provides aggressive yet smooth traction to give you the confidence and performance you need. Get longer life and better traction with the heavy duty Yukon Dura Grip Positraction.... Yukon Gear Dura Grip For Dana 44 / 30 Spline / 3.92+ 1975-1978 GMC K15 Base / High Sierra / Sierra Classic / Sierra Grande $900.89 |
 IN STOCK - DROPSHIPS YDGGM12T-3-30-1Yukon Dura Grip is a positraction limited slip differential that provides smooth yet aggressive traction, giving you the confidence and performance you need across a wide variety of terrains. The Dura Grip is engineered for long life and is completely rebuildable. Dura Grips are constructed with a h... Yukon Gear Dura Grip Limited Slip Differential for GM 12 Bolt 30 Spl 2.76-3.42 Ratio 1975-1978 GMC K15 Base / High Sierra / Sierra Classic / Sierra Grande $754.89 |
 OUT OF STOCK YDGGM12T-3-33-1Yukon Dura Grip is a positraction limited slip differential that provides smooth yet aggressive traction, giving you the confidence and performance you need across a wide variety of terrains. The Dura Grip is engineered for long life and is completely rebuildable. Yukon Dura Grips are constructed wi... Yukon Gear Dura Grip Limited Slip Differential for GM 12 Bolt 33 Spl 2.76-3.42 Ratio 1975-1978 GMC K15 Base / High Sierra / Sierra Classic / Sierra Grande $795.89 |
 IN STOCK - DROPSHIPS YDGGM12T-4-30-1Yukon Dura Grip is a positraction limited slip differential that provides smooth yet aggressive traction, giving you the confidence and performance you need across a wide variety of terrains. The Dura Grip is engineered for long life and is completely rebuildable. Dura Grips are constructed with a h... Yukon Gear Dura Grip Positraction For GM 12 Bolt Car w/ 30 Spline Axles / 3.73+ 1975-1978 GMC K15 Base / High Sierra / Sierra Classic / Sierra Grande $919.89 |
 IN STOCK - LOW YDGGM8.5-3-28-1Yukon Dura Grip is a positraction limited slip differential that provides smooth yet aggressive traction, giving you the confidence and performance you need across a wide variety of terrains. The Dura Grip is engineered for long life and is completely rebuildable. Dura Grips are constructed with a h... Yukon Gear Dura Grip Positraction For GM 8.5in w/ 28 Spline Axles 1977-1978 GMC K15 Base / High Sierra / Sierra Classic $908.89 |
 OUT OF STOCK YGLD44-3-30Everything about the Yukon Grizzly Locker is hardcore, its casing and gears, its advanced gear tooth design, and its impact on traction and performance. The Yukon Grizzly Locker is a mechanical positive-locking differential that's engineered for rock crawling, serious trail running, off-road racing,... Yukon Gear Grizzly Locker / Fits Dana 44 / 30 Spline / 3.73 & Down 1975-1978 GMC K15 Base / High Sierra / Sierra Classic / Sierra Grande $1,098.89 |
 OUT OF STOCK YGLD44-4-30Everything about the Yukon Grizzly Locker is hardcore, its casing and gears, its advanced gear tooth design, and its impact on traction and performance. The Yukon Grizzly Locker is a mechanical positive-locking differential that's engineered for rock crawling, serious trail running, off-road racing,... Yukon Gear Dana 44 Grizzly Locker Replacement 1975-1978 GMC K15 Base / High Sierra / Sierra Classic / Sierra Grande $1,062.89 |
 IN STOCK - DROPSHIPS YP MINSD44-30Yukon Mini Spools are a low-cost traction option for vehicles looking for full-time lockup. The mini spool installs into a standard open carrier in place of the spider gears and delivers 100% power to both tires at all times. These units are not recommended for street-driven vehicles. Full spools ar... Yukon Gear Mini Spool For Dana Spicer 44 w/ 30 Spline Axles 1975-1978 GMC K15 Base / High Sierra / Sierra Classic / Sierra Grande $207.89 |
 OUT OF STOCK YP MINSGM12-30Yukon mini spools provide the traction of a full spool at an economical cost.... Yukon Gear Mini Spool For GM 12 Bolt Car & Truck w/ 30 Spline Axles 1975-1978 GMC K15 Base / High Sierra / Sierra Classic / Sierra Grande $277.89 |
 IN STOCK - DROPSHIPS YP MINSGM8.5-28Yukon Mini Spools are a low-cost traction option for vehicles looking for full-time lockup. The mini spool installs into a standard open carrier in place of the spider gears and delivers 100% power to both tires at all times. These units are not recommended for street-driven vehicles. Full spools ar... Yukon Gear Mini Spool For GM 8.5in w/ 28 Spline Axles 1977-1978 GMC K15 Base / High Sierra / Sierra Classic $188.89 |
 IN STOCK - DROPSHIPS SL D44-30The Spartan Locker by USA Standard Gear provides reliable traction at a low cost. The Spartan Locker's patent pending design replaces the spider gears in a standard carrier case, does not use the thrust washers, and has a revolutionary spring-and-pin design that makes installation even easier! This ... USA Standard Spartan Locker For Dana 44 Diff w/ 30 Spline Axles / Incl. Heavy-Duty Cross Pin Shaft 1975-1978 GMC K15 Base / High Sierra / Sierra Classic / Sierra Grande $710.89 |
 IN STOCK - DROPSHIPS SL GM12-30USA Standard Spartan Locker For GM 12 Bolt Car & Truck w/ 30 Spline Axles 1975-1978 GMC K15 Base / High Sierra / Sierra Classic / Sierra Grande $734.89 |
 IN STOCK - DROPSHIPS SL XP-D44USA Standard Spartan Locker Replacement Cross Pin For Dana 44 1975-1978 GMC K15 Base / High Sierra / Sierra Classic / Sierra Grande $56.89 |
 IN STOCK - DROPSHIPS SL XP-GM12USA Standard Spartan Locker 12 Bolt GM Spartan Locker Cross Pin 1975-1978 GMC K15 Base / High Sierra / Sierra Classic / Sierra Grande $56.89 |
 IN STOCK - DROPSHIPS YP FSD44-3-30DNYukon Full Spools are a cost-effective way to convert a diff to 100% lockup. Installation is easy as they install in place of your differential carrier assembly. Each Yukon spool is made from high-quality 8620 steel and heat treated for additional strength. A spool is an outstanding choice for dedic... Yukon Gear Dana 44 Steel Spool Replacement 1975-1978 GMC K15 Base / High Sierra / Sierra Classic / Sierra Grande $406.89 |
 IN STOCK - DROPSHIPS ZP MINSD44-30USA Standard Gear Mini Spools are a low-cost traction option for vehicles looking for full-time lockup. The mini spool installs into a standard open carrier in place of the spider gears and delivers 100% power to both tires at all times. These units are not recommended for street-driven vehicles. Fu... USA Standard Mini Spool For Dana 44 w/ 30 Spline Axles 1975-1978 GMC K15 Base / High Sierra / Sierra Classic / Sierra Grande $151.89 |
 IN STOCK - DROPSHIPS ZP MINSGM8.5-28USA Standard Gear Mini Spools are a low-cost traction option for vehicles looking for full-time lockup. The mini spool installs into a standard open carrier in place of the spider gears and delivers 100% power to both tires at all times. These units are not recommended for street-driven vehicles. Fu... USA Standard Mini Spool For GM 8.5in / 28 Spline 1977-1978 GMC K15 Base / High Sierra / Sierra Classic $148.89 |
 IN STOCK - DROPSHIPS ZP FSD44-3-30DNInstalling a quality USA Standard Gear spool is a cost-effective way to get 100% lockup. Installation is easy as they install in place of your differential carrier assembly. Each USA Standard Gear spool is made from high-quality 8620 steel and heat treated for additional strength. A spool is an outs... USA Standard Steel Spool For Dana 44 w/ 30 Spline Axles / 3.73 & Down 1975-1978 GMC K15 Base / High Sierra / Sierra Classic / Sierra Grande $317.89 |
 IN STOCK - DROPSHIPS ZP FSD44-4-30UPInstalling a quality USA Standard Gear spool is a cost-effective way to get 100% lockup. Installation is easy as they install in place of your differential carrier assembly. Each USA Standard Gear spool is made from high-quality 8620 steel and heat treated for additional strength. A spool is an outs... USA Standard Steel Spool For Dana 44 w/ 30 Spline Axles / 3.92+ 1975-1978 GMC K15 Base / High Sierra / Sierra Classic / Sierra Grande $302.89 |