1999 you should just have to crawl under and reach spud on top of the transfer case.
I "think" it was some 2001, all 2002 & 2003 that did not have the spud.

 

I am wondering if it could be something else. I need to explore my possibilities. I noticed it making that noise a bit today in neutral. Wouldn't that not happen if it was the shaft? Is there anything on top of the engine that would grind. It doesn't do it all the time consistently . But it does do it all the time.

 

If you hear the noise while stationary it's not the prop shaft. Regardless, if there Is not grease fitting on the u-joints, replace or rebuild as soon as you have the means. No joke.

Back to the issue at hand. Possible an exhaust leak at the manifold flange?

 

Are you able to post a video of the noise? Might be moe helpful if we can hear it.

 

I would get up under the truck with it on and try to find where the source of the noise is coming from. Make sure its in park and the emergency brake is on. It could be an exhaust leak or the y pipe make be resting on the cross member where the y pipe ties into the muffler. Also did they put new metal gaskets in? Last make sure all three studs and nuts are in place where the y pipe connects to the exhaust manifold.

 

Due to the description of the sound being "grinding", I dont think it is an exhaust leak.

I say this because when I redid my exhaust, I didnt torque the manifold stud nuts to spec. A week later I found that 3 of the 6 had fallen off. The resulting noise is that of a diesel school bus...loud chugging rather than a strange grinding.

 

I will try to record the sound. It sounds pretty bad. I find it so hard to get a shop to do a good job any more. I am sure the mechanic heard it when he pulled it out and just said to hell with it.

 

Still waiting to capture the noise, it's hard because for the most part I need to be driving, and while driving I need to try an effectively capture the sound.

On a better note. It hasn't exploded yet.

If I had an oil change and the guy put in a quart or two more, could that be causing some noise? I did see two gallons of oil in jugs as well. someone could have been lazy and add more oil when i took it in.

 

Ok.. So I went back to the mechanic...

Man am I a happy camper. When they put back on the exhaust it was very close to the frame, so what would happen is that it would heat up, and then make contact with the frame at certain times while driving and just rattle, buzz, and vibrate like crazy.

The mechanic re-set the pipes and now everything is peachy..

Thanks guys!