Tractor Repair: additive for CASE MX220, limited slip, exact size

Question
Dear sir,

can You tell me, please, how much LIMITED SLIP ADDITIVE is
pouring into front differential house of CASE MAGNUM MX220?
Which way is the best to put additive in mentioned house
(should I mix it with 80w-140 oil and then pour it into
house or is it enough to put additive first and than oil?)
Thank you,

respectfully  
Steve

Answer
Hello,

  We get our additive in small bottles, don't know the exact size, about 12 ounces I would guess.  I don't know the part number for these bottles off hand.  We cut the top off the spout of the bottle and squirt the entire bottle into the front differential, then fill it with 85w140 oil.  Shake the bottle of additive first to mix it well before using.