My noise hunting thread: drive shaft?

[tk45s]

OK, I just put 500 miles on a 99 LC with 98,000 miles. I'm looking at two problems now:
1. A low noise/vibration when accelrating, clearly felt through gas pedal;
2. A high pitch chirping from front side, seeming also happens when accelerating.

So, I dug out old posts on drive shaft and today crawled under the truck. Two preliminary questions:

1. The front/rear shafts do not have any play EXCEPT that all 4 end yokes (directly connected to front/rear differential and t case) can rotate a bit. Also the spline where the rear shaft changes its length also has this kind of "play". Though the noise does not seem to come from them, I'd appreciatre someone to confirm that if this is normal.

2. The thinner part of the rear shaft was covered by a thick layer of black grease. When I tried to detect play some of the grease was wiped off. Is it OK or a bad thing since rust could develop on the exposed part?

So far not to the noise/vibration curing yet. Just two questions in my mind now. Next step I will get jack stands and a greasing gun and play with it a bit. I also noticed the discussion on U-join phase setting and will take a look at my truck next time.

BTW, I heard that it could be tough to unmount the grease gun from a zerk fitting. Any tips here?

Thanks for any suggestions!

 

[NMuzj100]

#1 is a known issue with the T-case. There is a TSB but it's an expensive fix and most just live with it when out of warranty. For details see the TSB thread in the FAQ.

#2 maybe wheel bearings? Or squeeling brake pad ?

I haven't had any problems with the zerks but I use a hose-type flex head.

 

[tk45s]

Thanks a lot! I also think the chirping sound may be from wheel bearing. I'll try to lube them.