I have scoured the internet and this forum, and found quite a myriad of recommendations for what weight and type of differential oil to use. It seems most agree they need two slightly different weights with synthetic a must in one. But I'm still not sure which way to go yet. So what do you guys suggest for the front and rear differentials?

Thanks in advance for your thoughts.

 

Just to give you guys what I have found (I have no expertise at all); so far, in my notes, I have most of the other sites and forums stating:
Rear Differential - SAE 80W90
Front Differential - SAE 70W90
There seems to be a overall nod towards synthetic over old school petroleum, but no "must do" kinda thing.