ok, cold morning. cold start. takes a couple more cranks to get it started and then my dried out starter making the wheeeeee sound for about two seconds. i warm up for 60 seconds and bust it into R to pull out. release the e-brake. Then I get a noise from the engine bay that goes from a high pitched humming noise and then gradually diminishes in pitch and volume, all in sync with the rpm's going down as well.

i know the description could be better, but i really can't think of any other way to really describe it. This only happens when in R, when I put it into D after backing out, no noise.