Real axle lube?

Hello, yes these did require a friction modifier. The most important thing here is to get the correct weight oil that has a GL-5 rating, and then add a friction modifier to that in the case.

William

Do you have any suggestions on what weight the gear oil should be and what friction modifier to use?

I have some additional information for you. The tag on the axle reads S744G which equates to an 8.5 3.55 gear ratio.Looking at another chart it says to use Motorcraft SAE 80W90 premium rear axle lubricant and either 4oz of ESW-M2C118-A PART#C8AZ-19B546-A friction modifier for a complete refill of a Ford traction loc rear axle or 6 oz of WSP-M2C196-A part# F3TZ-19B546-MA friction modifier for a complete refill of a Ford DANA Traction Loc axles.Now all I have to do is figure out which axle I have either a Dana traction Loc or Ford traction loc axle. How can I tell the difference. Also I see a 75W140 synthetic axle lube, can I use that instead and if so do I need a friction modifier with it. I know this is a lot to digest but I need help. Thank You.

Sounds like the Ford TracLoc axle to me. It will likely be better to use the 80w90 GL-5 rated oil with the friction modifier. Some of the 75w140 will have a modifier in it but there's always a debate on the amount of modifier that it contains. So that decision will ultimately be up to you.

William