I have a question for those who are more mechanically inclined than me (everybody). Just yesterday I noticed that my truck is making an oscillating click/chirping noise that is relative to the amount of juice I am giving it. Then when the O/D kicks in the noise disappears. Also if I let off the gas the noise winds down. When I noticed that it went away when O/D kicked in I tried and experiment. Got up to about 40 mph and threw the truck into Neutral, the noise went away. I am taking it to the shop today but I wondered what your impressions would be.

 

Mines doing the same thing, even in O/D, usualy under some load (going up hill, starting off) when I come to a stop I can hear the chirp "wind down"
could this be TC related?

 

Could be bad u-joints. I have had them make a noise like that, especially when they have a load put on them.

 

Yep, it was the rear u-joint. I took it to a trans shop and they quickly diagnosed the joint, it was just like a gravel road, dry-dusty and washboard surfaced. I've replaced about 10 of those things (in Chevies) and this one sounded nothing like those. The new one has a zirk with lots of new grease.
and waaaayy cheaper than a new TC