2005 Dodge Dakota SLT Squeaky Noise

I recently purchased a 2005 Dodge Dakota SLT with 50k on it. The truck is in great condition inside and out. I have noticed depending on certain days, different weather conditions that it will make a squeaky noise when going over the bumpy roads. First thing that came to my mind was the sway bar end links. I purchased them from NAPA and installed them. Still the truck is making this noise. Any idea what it can be? Almost sounds like it is in the rear of the truck but hard to actually pin point the location. I have tried with all windows down I cannot tell.

Sound is exactly like this video:
http://www.youtube.com/watch?v=mE6yFHFvbYs

Any ideas? Its driving me crazy!

Have you greased the front end lately? I know some Dakotas don't have grease fittings but I bought a grease needle at the parts house and use it to service my Dakota.

Great what parts? I just put new front end links on... I was inspecting the rear links and there is a lot of play with them... Is this normal? Almost like there is no bushing.

Anything with a rubber boot such as upper and lower ball joints and tie rod ends. Seems like anything that feels loose is a suspect in making a noise.