I was waiting in the on ramp to the parkway the other day and decided to gun it when I saw an opening. The car didn't really take off the way i expected it to but revved up to 4000 then launched. About as fast as I could think "that wasn't good" It started making a loud whining noise that sounds like its coming from under the back seats. The faster i go the louder it is. Sounds like something spinning out of balance. Could i have bent the driveshaft? It's a 99 grand Cherokee limited with quadra drive.

 

When I go to the gas pump for a fill-up.....Waka-Waka!

 

Did the jeep make any other sound? Like a Pop or a snap? Have you checked all fluids. Trans, transfercase, differential?

 

Just did all the fluids a couple months ago for the winter and checked the tranny fluid. The sound is def a result of that situation but the car drives and shifts smoothly at all speeds. I don't recall any other sounds.