Heavy Vibration on Liberty

Hello all,
I have been experiencing a very rough vibration on my Jeep Liberty when travelling at speeds over 65 kph. The viration can be felt through the seats, console, floor and the steering wheel. At first I tought it might have been the tires out of balance but I had 4 new ones installed yesterday and the vibration is still there. I have noticed though, that the vibration only occurs during acceleration at speeds over 65. If I let up on the gas pedle the vibration stops. I would like to get some possible suggestions before taking it into the shop.
Any help would be great.
Thanks

sounds like a driveline vibration possible drivershaft or cv axle if all wheel drive

You didn't say how many miles or what year your Liberty is. I'd guess a Ujoint also.

Sorry about that it is a 2002 with 157,000 km on it