I found this and thought it would be helpful for some people on changing out the diff fluids and what thick and thin does.

Front
Thinner :

increases steering into corners (off-power)
if oil is too thin the steering may become inconsistent, especially it can lose forward traction (and steering) during acceleration out of corners

Thicker:

increases stability into corners during braking
increases steering on-power at corner exit
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Center
Thinner:

front wheels unload more during acceleration
decreases on-power steering (reduces oversteer)
easier to drive on rough tracks
if a high-power engine is used you could waste too much power and sometime “cook” the oil in the center diff erential because it “overloads”

Thicker:

more all-wheel drive effect
better acceleration
increases on-power steering (reduces understeer)
better suited on high-bite, smooth tracks
car can be more nervous to drive especially if a high power engine is used - you might need to be smooth on the throttle

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Rear
Thinner:

increases cornering traction
increases steering into corner
Thicker:

decreases rear traction while cornering
reduces wheelspin