So ive been trying to figure out what the noise is but I just cant seem to find it.......I doesnt really happen driving around the city as it does the highway, It doesnt start rattling until I shift into 4th gear and then up into 5th and then itll do it on/off down the highway.........everything seems to drive fine, just dont know what it could be.

 

I'd say it's your tranny trying to shift into 5th.

 

i dont think its that, Its right when I shift down into 4th, not even ready for me to shift up into 5th.....anybody else know what it could be?

 

How many miles on clutch/pressure plate/throw-out bearing?
I'd say, throw-out bearing.