Which oils to transfer box and and differential

[lateshow]

Just wondering, Mitsubishi says use GL-5 oils with viscosity 75W-80 or -90. Mobil 1 recommend SHC1 which meets requirements. Castrol recommens 75w-140 for rear differential, GL-5 and syntrans 75w-90 for transfer box, syntrans is a GL4 oil. Now I have pput the same syntrans GL4 to both transfer box and rear differential, am I ruining them, what should i do? Should i go back to mobil shc-1? Or just change the rear differential to castrol 75w-140??? What oils have you been using?

[Ryan]

I've used 75W90 in both transfer case and rear diff in two VR-4's with no issue.

[Gly]

change it to what mitsi recommend for there parts, GL5
in both transfer case and rear diff

not what the oil companys recommend