Need help diagnosing grinding/squeeking/squeeling sound
Recently my 2005 5.7 Limited GC started making some very strange noises when the truck is cold and has been sitting for some time, such as overnight. The issue I have is that upon starting to drive away a loud grinding mixed with squeeking and slight squeeling noise can be heard even over and above my exhaust (which is loud) coming from the front end seeming louder on the drivers side. The noise is ONLY when the truck is under load, if you let off on the gas the noise stops altogether, I tried accelerating with the brakes applied to ensure it was not just something stuck between the pad/rotor, no difference. Also the noise increases in its rate/speed as you accelerate.
The other thing I've noticed is that as soon as you get the truck up to temperature, and have driven it for around 20mins+ the noise goes away entirely, even under load it cannot be heard. I've also noticed that my shaking at 100km/h+ has also seemed to have gotten worse with this new sound/issue.
Also of note, the sound does not present ever if you go in reverse.
Kind of at a loss as to what it could be. Had my mechanic check out the front differential, as well as the transfer case and rear differential with a stethescope, as well as checking for any play in the drive shafts and axles. The only issue he found was that there was quite a bit of play front to back and up/down on the rear driveshaft where it connects to the rear diff and that with the stethescope, he said that the rear diff needs to be rebuilt.
Could this cause the noise in the front as well as the horrible shaking of the wheel at highway speeds?
Any thoughts or ideas would help as even he is unsure exactly the cause of the noise upfront.