Differential lube advise wanted

[Lloyd10977]

Differential lube advice wanted

I have a 1995 Explorer limited with 3.73 rear differential with TractionLok. I am planning to replace all fluids in tranny, xfer case and diff with synthetics by Royal Purple. The vehicle was well maintained before I purchased it but I am unsure what type of fluids were used.

What I need to know is if it is still required to add friction modifier in the rear diff when using the Royal Purple brand? The website seems to hint that the addition of friction modifier is unnecessary.

 

[bmxking5]

Not positive, but I am pretty sure that you won't need anything else if you are putting in synthetic.

 

[Lloyd10977]

Come on guys, I know someone, somewhere must have some experience with Royal Purple in an OEM Traction-Lok differential. Even if you have experience with ANY synthetic lubes, please speak up. Thank you.

 

[prozachappy]

I run the Royal Purple in my factory LS. Very happy with its performance. It does say no friction modifier needed, but I had some left over from last change and went ahead an added it. I'm not due for awhile...but I'll prob use the RP again, without the additive.

 

[Mbrooks420]

If your 95 has any miles on it it is likely the LS is sloppy enough that you wouldn't need friction modifier anyways.

 

[Lloyd10977]

Thanks for the advice guys. I've decided to go with the Royal Purple 75w90 because the light weight would help (even slightly) with fuel economy and cold weather and it has enough of the friction modifiers needed. And since I do mostly highway driving without towing a trailer, the need for the heavier viscosity of 85w140 should be unnecessary. This based on information gathered from the BobIsTheOilGuy site.

BTW, even with 94k miles, the TractionLok lsd works quite well.