What gear oil in Sure Grip Posi?

[rlem1977]

Multi-Purpose Gear Lubricant, GL-5, like MOPAR Hypoid Lubricant (PN #4318058) or Valvoline 80w-90 HP Gear Oil. In Sure-Grip Differentials, 4 ounces of MOPAR Hypoid Gear Oil Additive Friction Modifier (PN #4318060), or equivalent, is needed.

 

[MW 413]

Even though some of the synthetic gear lubes say they have the posi or sure grip additive already in it you will find out that you will still need to add the posi additive. I use the Motorcraft Ford additive in any of the lubes. Clutches will chatter in tight slow turns on most units without it.