Sounds like something hit your fan. (Are you missing a cat?)

As long as the fan blades are not hitting the radiator, you can get by. The
wobble will decrease engine performance, but I can't imagine you would
notice it unless you are the type that notices a pea under your stack of 100
mattresses.

Here's an obvious solution: If "it looks as if its loose at the shaft of the
fan," try tightening it.

don't know about the 4x4 but my truck from that era had a fan clutch
and it may be failing. If it is just direct bolted to the water pump
or whatever I'd replace it rather than have the imbalance take out
the pump.