Differential fluid change - do I need friction modifier?

[Yukon Joe]

Maybe that is why some guys blow the rear end of the 2010's... lol...

Yukon Joe
www.RUNRAPTORRUN.com

 

[Madcowranch]

2010's are indestructible. You could fill the diff with sand on a 2010 and it wouldn't hurt it.

 

[Ruger]

^ Yeah, and sand also makes a suitable substitute for KY.

 

[Nick@Apollo-Optics]

2010's are indestructible. You could fill the diff with sand on a 2010 and it wouldn't hurt it.

So why don't you just throw some WD-40 in there and call it a day, *****.

 

[badmonkey]

Just to add to this discussion, the 2014 SVT supplement specifically says to NOT add any friction modifier.

 

[Humvee21]

Just to add to this discussion, the 2014 SVT supplement specifically says to NOT add any friction modifier.

Very interesting! I just took a look and yup, the rear specifically says not to add it, but the front you must (since the torsen is a LSD I would assume).

https://dl.dropboxusercontent.com/u/12246588/2014 raptor supplement.pdf

Also, the 2014 raptor supplement definitely seems more "official" than the previous years'. Meaning that I think they worked out the typos and added more detailed info specific to Raptors

 

[Yukon Joe]

Hmmm... So what harm is it to add the friction modifier to the rear diff?

Yukon Joe
www.RUNRAPTORRUN.com

 

[Ruger]

Just to add to this discussion, the 2014 SVT supplement specifically says to NOT add any friction modifier.

That's weird. 2011, 2012, 2013 manuals all say to use friction modifier. I bet the rear ends are identical across all 4 years, too. I think that the FRF Leadership might consider asking Ford for official clarification. Guys?

 

[hosseface]

Alldata specifically says do NOT use Friction Modifier in ELD (electronic locking) differentials.

 

[Madcowranch]

The only 75w-140 synthetic I've found w/o a F/M is Redline.