Got a little over 700 miles on my 05 Tacoma 4x4 and want to run synthetic oil in the engine. Can I switch now or do I need to run dino for a while?

Back, don't run fully synthetic oil until the first scheduled oil change 10,000 miles? or one year. This will allow engine and piston rings to bed in properly,which they won't do on synthetic, and avoid having the engine use oil when you switch to synthetic. At the first 10K service get the gearbox oil changed as well to get rid of all the bits of swarf, and the gearbox should subsequently have a long life.