Re: NV247 TC fluid
Welcome to the garage.
I doubt that Dexron 3 can be used in the T-case. It probably will lubricate the T-case, but the special fluid is there to prevent clutch chatter inside the progressive coupler. When the WJ debuted in '99, the NV247 was filled with ATF+4, but due to the problems they encountered with the clutch chatter, they looked into other fluids. Mobil 424 was found to do the job well and was sold as the special Mopar NV247 fluid. I never heard that the Dexron 3 is compatible with Mobil 424.