Description
Based on our Transmission Fluid Change Kits developed over 10 years ago, the BG Ultra Guard Differential Fluid Kit, with your choice of Viscosity and Additive Packages, allows you to perform a differential service your S550 or S650 Mustang that did not come equipped with Transmission and Differential Oil Coolers.
We recommend the 75W-90LS for all street driven Mustangs.
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.
We include 2 Quarts (64oz) of Ultra-Guard, a pump, dipstick, Teflon sealant tape and Color Instructions.
Video
Fitment
Fits All 2015-2026 Mustangs without Factory Differential Oil Cooler.
Installation
Specs
Specifications: BG Ultra-Guard LS 75W-90
| Test | ASTM Test Method | Typical Test Results |
| Specific Gravity @ 15.6°C (60°F) | D1298 | 0.8605 |
| API Gravity @ 15.6°C (60°F) | D287 | 32.9 |
| Density, U.S. lb./gal (kg/m³) @ 15.6°C (60°F) | D1250 | 7.174 (859.6) |
| Viscosity, cSt @ 40°C (104°F) | D445 | 97.17 |
| Viscosity, cSt @ 100°C (212°F) | D445 | 14.43 |
| Viscosity Index | D2270 | 154 |
| Viscosity, cP @ –40°C (–40°F) | D2983 | 95,333 |
| Pour Point | D97 | –40°C (–40°F) |
| Flash Point, COC | D92 | 196°C (385°F) |
| Color | D1500 | 2.0 |
| Color | Visual | Yellow |
Kit Components
2 - 32oz Bottles of BG Ultra-Guard 75W-90LS
1 - Gear Oil Pump
1 - Dipstick
1 - Roll of Teflon Sealant Tape
1 - Color Printed Instructions