anyone? any ideas or anything, really need help, this is my DD

I had a really bad hum/vibration at 30 and up to 60 and swaped out the u-joints and still had it. Got under it again to check my rear leaf spring and noticed my exhaust braket in the back was broke and the exhaust was vib/rubbing on the side of the hitch.

It only happens at fast acceleration in low speeds

Bump

is your jeep auto or manual? does it do it when you gradually accelerate or just on hard acceleration

It's and auto and it does it with hard acceleration

sounds to me like something is slipping then. if its only doing it under hard acceleration then that tells me when there is a load on it its slipping. maybe your tranny is bad. not sure

I would pull the front shaft and then drive around to see if it still makes noise.

what is that going to do if you dont mind me asking?

It makes more of a ratchet sound then a grinding

Any loss of power? I had a similar sound that after I got stuck on a rock and after I power thru it, it started to make that noise. The longer I drove the more it lost power. After tearing it apart three times and changed flex plates I took it to a transmission shop and the guy took it around the parking lot came back and handed me the keys and said "torque converter"! I think it cost me about $200.00 and I installed it. So you might take it to a shop and ask them to listen to it and get there opinion. If that is it make sure you change the fluid and filter, when I did it the fluid in the pan looked metallic. It took three fluid changes before it looked clean.
Hope this helps!

Yeah it feels kinda sluggish when I'm in first gear

You might give that a try and please let us know what they say and how its going. There are magnets in the bottem of the pan and mine had alot of metal shavings on it. Good luck.

You think they'd charge to just drive it around for 5 mins or so??

On the TC shift rod, put the case in 2HI and loosen the trunion nut that holds the rod in position. Then, put the shift handle in the 2WD position and tighten the trunion nut back down.Try that to check your adjustment.