Hey guys. First post. I just got a 2004 Ford F150 Titan 5.4V8 with a little over 150k miles and I am trying to figure what the problem is with this noise I am hearing. It was from my dad who passed away, and he took pretty good care of it. Anyway I am running into a few small issues here and there and need some input.

When I am driving and come to a stop, then make a turn, I hear and feel a slightly quiet rumble noise from the rear axle that sounds like grinding or slipping. It only lasts for about one second, or for as long as I am turning. It doesn't sound horrible, but I know something is probably not right.

My brother, who had the truck for a little while, informed me that it was the rear clutch pack going bad. However, he is not a mechanic and I am hoping he is wrong. A mechanic friend of mine said that the lug nuts could be loose or it could also be the wheel bearings going bad. So we jacked up one of the rear ends and I pushed and pulled my wheel and felt just a little bit of play. I then tightened my lug nuts and there was no play. However the truck still makes the noise when turning.

Is there any way I can be sure which of the two problems it is (bearing vs clutch pack)?


Other notes:
- My ABS light flashes when I first start driving my truck and then remains on. I read in another thread that this can indicate the clutch pack problem.
- This truck recently had a front wheel bearing replaced... I assume they would have checked all the bearings though..
- A few days ago, I was driving and I heard something like metal slipping out and then I heard what sounded to be a piece of metal landing on the pavement and bouncing away... I thought "oh no..." Could that have been a wheel bearing? Hopefully it's just something I hit on the road but I doubt it.

Any help or input is very appreciated!
EDIT:What the hell is the difference between the rear clutch pack and rear wheel bearings? Aren't they in the same spot? Same thing? Similar things?..