The New Process 231 transfer case is one of the most common and durable transfer cases ever produced. Found under Jeep Wranglers, Jeep Cherokees, Dodge Rams, an
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The stock case has more ribs on it:
Its been so long since I installed the 4:1 on my XJ, Id forgotten the front case was different.
Not sure I would trust the outside visual for a confirmation, but certainly would lean towards it being a 4:1.