Rear Diff Temperatures?!?

[Crumm]

crumm, I hate to ask, what exactly are you doing polishing the aluminum cover? Am I going to need to make some mod of a new cover I have already put on to meet the standard you are setting?

To make it look purdy

 

[6LMonster]

Crumm,

Since you have an OBS as well, what fluid are you running? The book calls for 80W90, but I was thinking of putting in 75W140.....What do you think?

Also, I will be using Royal Purple.

 

[Crumm]

Crumm,

Since you have an OBS as well, what fluid are you running?

I have ran both Mobil 1 Synthetic Gear Lube 75W-90 and Mobil 1 Synthetic Gear Lube 75W-140. As far as gear lube goes I don't think the rear-end cares.

I also add the Ford OEM limited slip friction modifier when I change it but I don't know that it does anything or not since the Mobil oil has them in it..

Mobil 1 Synthetic Gear Lube 75W-140 and 75W-90 contain special friction modifiers designed for limited slip-type differentials. In most applications, the addition of special LS (limited slip) additives is not required. For axles requiring the highest level of limited-slip performance, OEM specific LS additives can be added to this fluid.

 

[6LMonster]

Right, the Royal Purple says that it has the Modifiers in it as well.

 

[WD40]

Don't add it if you use Royal Purple .
It will be to much and your
pos-a-track will not work as well.
At least that's the way it is on my 06.

 

[Crumm]

It will be to much and your pos-a-track will not work as well.

Hmmmmm Wonder if that is why my limited-slip is more like unlimited-slip?

 

[MidwestOffroad]

you dont need any friction modifires with top end oils like Royal or Amsoil. unless you get chatter.

the 08 cover will fit all 10.5 10.5 rears and powerstroke shop is the best deal. on them but i would recommend getting some nice stainless bolts (longer) and washers as it is thicker than the stamped steel one.

 

[Tx_Atty]

I just did the change and used the RP fluid and put on the 08 diff cover. Works and looks great.

 

[Tx_Atty]

Crumm, what are you doing to polish it? How, that is. Take a pic too so I can see if I wanna be like you.

 

[MidwestOffroad]

make sure you coat it with zoops or something or it will tarnish in a week.