I have an 07 4.7 flex with 63k. Sometimes the 4wd would go into lock position right after I started it. I drove( and towed my 00 Grand Caravan) from LA to Arkansas last month. While driving back from Kansas City the 4wd light began flashing going 70. After a minute or so it stopped. about 50 miles later I began to smell heavy wt oil like from an axle of transfer case. Check it and the hose from the case coming up on the drivers side had fluid coming out and leaking but not while the engine was off, it must have been during driving. I was 45 miles away so I hobble back at 55. When I pulled into my driveway, the engine was fluttering between 1k and 500 rpms. THe smell of 90 wt type oil apparent on under the hood. The 06 manual ( could not find an 07) states clearing the transfer vent or replacing the hose. Is the vent at the top of the hose leading up next to the block? Or is this another problem.? Also I have the ever-so-common gas cap light on and a code which reads a vacuum leak of some kind from the purge or something like this.
Any ideas??
Bummed at 60k

Oh and I could hear a "whirring" sound of some sort as I pulled up but not in the engine.
Thanks guys