04 PST 4x4 F250- 75-140syn in rear axle, OK to use same in front axle? Couldn't find anything by searching. Also How much friction modifier to add? service book says 8oz in one place and 4oz in another. Just in rear axle? in looking up parts, there are always references to which type of axle is in the vehicle, both front and rear. Dana, Spicer, traction lok. How do you tell which that you have?