Originally Posted by skibumdc
Can't you just an oil with a friction modifier regardless?
If you have an open diff it won't hurt anything, right?
And if you have a limited slip diff it's the right fluid.
I'm about to do the GF's car for the 30K service and figured I'd look for a 75W-90 and add a modifier if needed, but I don't think it is.
Yes, you can use an oil with the friction modifier regardless. That's what I ended up doing. I just went with the Redline 75W90 and it has been fine. Here is a response I got from Red Line also:
Name : XXXXX
>Email Address : XXXXXX
>Make : Infiniti
>Model : G35X
>Year : 2004
>Engine Type : VQ35DE (3.5L)
>Differential Size/Type : Rear:Nissan R200 (Open) Front:Nissan F160A (Open)
>Transmission Type: 5 Speed Automatic
>Issues : N/A
>Recommendations : I am looking at what the best fluids would be for
>my differentials and transfer case. For the differentials, is the
>75W90 or 75W90NS the preferred? Also, for the transfer case Nissan
>recommends Nissan Matic D ATF, which I do not see any equivalents in
>your ATF guide. It does say you can use Dexron III/Mercon though.
>Basically I would like to know which is better with the transfer
>case: Your D4 ATF or D6 ATF. Any help would be appreciated.
Thank you for contacting Red Line Oil, in your Infiniti differentials
I would recommend the 75W90 and the D4ATF in the transfer case.
The 75W90 is prefered in the differentials as it contains a friction
modifier for friction and temperature reduction. The D4 is a suitable
replacement for the Nissanmatic D fluid, the D6ATF is a lower
Red Line Oil