Rear diff service

[mjonesjr]

If you put synthetic fluid in the diff you will NOT have to add the friction modifier as all synthetic gear oil already has the friction additive in it.

 

[lincolnlocker]

If you put synthetic fluid in the diff you will NOT have to add the friction modifier as all synthetic gear oil already has the friction additive in it.

ummmmm..... are you sure about that.... i have amsoil and it requires it!!

 

[mjonesjr]

ummmmm..... are you sure about that.... i have amsoil and it requires it!!

Then Amsoil is the only synthetic gear oil that I have ever saw that required it. I bet if you look on the bottle it will show it includes the friction modifier.

Another reason not to use Amsoil (sorry, not a fan).

 

[lincolnlocker]

it may be added to most but so far i have never heard of anyone NOT adding it if needed.... why take a chance.... especially if your towing heavy and the clutches lock up and you snap a axle shaft turning a corner...

 

[Diesel_Brad]

If you put synthetic fluid in the diff you will NOT have to add the friction modifier as all synthetic gear oil already has the friction additive in it.

That is a load of crap. I dont know where you heard that from. Says right in the FORD service manual to put in the friction modifier then fill with synthetic fluid

 

[Tom S]

I actually would not go full boar on added friction modifyer will sythetic. Maybe start out with half or something

 

[mjonesjr]

That is a load of crap. I dont know where you heard that from. Says right in the FORD service manual to put in the friction modifier then fill with synthetic fluid

Somebody needs to go read a bottle of synthetic gear oil.