Won't come out of 4x4 unless I stop and put it in reverse a short distance.

The fluid is new as of five years ago when I replaced all fluids with 100% synthetic and I don't use the 4x4 all that often except on winter roads and pulling the boat out of the water. Should be good still?

Yes, I do that from time to time and have had no problems with it ever until this winter. I hunt all year and any time I'm on a dirt road I put it in 4x4 for that exact reason. Still looking for an answer to the problem though. I know there is a small pump that puts the gear into 4x4 and I can hear it working when the lever is pushed forward as it should, but I don't know what takes it out of 4x4 when the lever is pulled back int 2WD. Should the pump kick in for that as well or is there a spring or something?

You stated "I don't use the 4x4 all that often.....etc"!! Most likely in the front differential or the hubs but i can't say!

You are correct. My mistake. I should have been more clear about that part. :)