My first question is what viscosity of differential oil should i be using? I live in michigan and it gets really cold here. Today i drained the rear oil and it came out really thick. Also i have a 700r4 tranny. when i have it in neutral and turn the drive shaft towards the drivers side its really easy, but when i turn it towards the passanger side it is really hard to turn, is this normal?

 

1.The usual stuff; 75W-90 or 80W-90. Avoid the super thick stuff like 85W-140. I'd suggest Mobil 1. Takes about 2 quarts.

2. Not sure which way you mean, driver's side vs pass side; but if you imagine looking at it from the front, clockwise is forward, CCW is reverse. Some degree of difference is normal, with forward being the easier way. If the car works and drives right and causes no trouble backing up then it's fine.