You will likely get away with no panhard on a 2" if you have standard duty srings. If you up-rate the springs I would expect it will be needed. Do the lift though and see how it settles after a couple of weeks. Once it has settled stand behind and infront of the vehicle and compare how far you tyres sit inside the gaurd each side, you will be able to see if the diff is centered under the car. If it is off to one side then you should correct it with a panhard.