I've got an annoying squeaking or cricket chirping noise driving over 30mph that I can hear with the windows down. Not terribly loud but plenty loud to drive me nuts. It sounds rotational like a ujoint, but the thing is three weeks ago I installed a new non greasable spicer joint on the rear shaft at the transfer case and about a year ago I installed two greasable moogs on the rear shaft. (just replaced the one at the t case with the spicer because it looked to have some play.) I checked the joints yestersay again and everything seems tight, I also greased the moog joint at the axle and the noise remained the same. My front hubs are tight and I see no leaking from either of the rear axle seals or diff cover. I know one thing to do would be to get the rear of the truck off the ground and bring it up to 30mph and listen for the noise but doing that in a gravel driveway with a 7000lb truck doesn't seem to exciting to me. I will note that the spicer joint I just installed seemed a little tight but I hit both ears on the shaft and freed it up a little bit before putting the shaft back on, it wasn't tight as if it were bound but it wasn't very loose either. What's yal's expert opinions?? And the noise wasn't there until a week ago.