Nukeiridium,

Came to pretty much the same conclusion after contacting Eaton. Here's a copy of the message: 24 Oct 2009

Me -
I would like to know if your company makes a drop in locking differential that will fit the 1998 - 07 KIA Sportage 10 Bolt, 28-Spline 4.44 rear end. other than the Eaton Posi: 19536-20.
I am part of a select few 4x4 off road enthusiasts that have selected the Kia Sportage as our vehicle of choice. We are very intrested in upgrading our rear differentials for this use. And your assistance on this matter would be greatly appreciated.

Tom Sape, Eaton Automotive Group,
(248) 226-6925
My apologies as I was told that our aftermarket team got back with you. Eaton does not offer differentials for this vehicle.