If the water was that deep you really should change all fluids... diffs, radiator, oil, tranny, transfer case, maybe even brakes and power steering if you want. Your vent lines may have been under water and that could contaminate the fluids in your housings. It would also be a good idea to get things lubed up again, and get the bearings re-packed. Also, keep an eye out for leaks cuz if the water was dirty enough it could cause problems with seals after constant grit wearing into rubber. I have used 3-in-1 oil on noisey pulleys (the bearings, not the grooves) in the past with great results, and maybe try out some belt dressing on the belt too. Good luck, I hope it isn't anything too serious!
Sent from my "two hands on a keyboard"