Based on our Transmission Fluid Change Kits developed over 10 years ago, the BG Combo Kit includes our world famous Syncro Shift II Kit with your choice of BG Ultra-Guard Differential Fluid which allows you to perform a complete driveline service with 1 kit for your 1979 to 2010 Mustang.

We recommend Following Ford's Guidelines and using the 75W-140LS Fluid in all Solid Axle 8.8" Mustangs. We do offer this kit in 75W-90 for those that require a lower viscosity oil for their application.

BG Ultra-Guard® LS Full Synthetic Gear Lubricant is a universal, full synthetic API GL-5 rated gear lubricant blended to SAE 75W-90 viscosity. It provides the ultimate protection for driveline components, especially those requiring limited-slip function. It is formulated for increased thermal stability, improved seal performance, quieter operation, and unsurpassed protection against wear, pitting, and corrosion.

BG Syncro Shift® II is the foundational chemistry we rely upon. We have shipped thousands of quarts of this product to every corner of the world.
BG Syncro Shift® II is an API GL-4 gear lubricant blended to SAE 75W-75 viscosity and may be effectively used in all vehicles where engine oil, ATF, or GL-4 gear oil is specified as “service fill” for manual transmissions. 
BG Syncro Shift® II Full Synthetic Gear Lubricant is specially formulated for manual transmissions, transaxles, transfer cases, and Haldex units. It is a full synthetic API GL-4 gear lubricant that provides unmatched film strength and wear protection. It provides exceptional resistance to mechanical shearing, has excellent low-temperature fluidity, and is safe for all steel, brass, and copper alloys. 
BG Syncro Shift® II is an API GL-4 gear lubricant blended to SAE 75W-75 viscosity and may be effectively used in all vehicles where engine oil, ATF, or GL-4 gear oil is specified as “service fill” for manual transmissions. 
 We include 1 - 96oz (2.8 liters) Container of Syncroshift II, 6oz of MGC Additive, a high volume fluid pump, 3 Quarts (64oz) of Ultra-Guard, a pump, dipstick, teflon sealant tape, Differential Cover Sealant and Color Instructions.