97 f150 clicking on acceleration

97 f150 4.6 l automatic 2wd, clicking noise when accelerating in gear. doesn't do it all the time and doesn't do it in park. checked fluids and they are fine. any ideas? don't know if this is related or not, but does seem to shake a little above 60 mph. over 300,000 on body, 150,000 on motor. thanks for any help.

Check the U-joints on the driveshaft.

My truck had a very similar issue. It would click mostly while accelerating, sometimes in park but never when revved in neutral. I took me the longest time to figure it out. Turns out it was the starter. When I pulled the old starter out the gear would slide freely back and forth. So I guess it was sliding forward and 'tapping' the flywheel ring gear. Upon replacement it hasn't happened since.