Ok, what did I almost tear up driving 65/70 in 4 wheel drive

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I drove into my friends yard and almost sunk. So I did not want to tear up his yard so i put it in 4x4. 4 high. after i parked, I forgot i had it in 4 high, but i did put my hubs in free mode after i got off his yard. long story short,
I drove 45 miles about 65/70 with my hubs in freemode and my shifter in 4 high.
In normal driving conditions you cannot tell its in 4 wheel drive mode. On the freeway i did feel a slight vibration. When i got home I had what looked to be ATF fluid on my tailgate and all over the bottom of the truck, not severe but just coated.

truck is back in 2 wheel mode and runs just fine, But if Im correct, your never suppose to drive in 4x4 mode on concrete. So can i ruin anything, or if something was gonna break i guess it would have already broke huh?.
I have taken my truck to the car was and wash underneath, no oil leaking now, but i need to make sure there is oil in the TC. What type of oil do i put in the 208 TC?? Thanks