Re: HELP! My jeep is shaking!
Not only that, but you have four "u-joints" in the front of your vehicle. There are two for the driveshaft and one for each side of the axle. If the axle U-joints are in need of replacement, then you will notice a clicking noise when you make sharp turns, not with straight forward movement.
Also, 3 months would most likely be a good time to balance your tires. Whether off-roading or not, i bet you hit some pot-holes or bumps in that time. Balancing can only help, also tell the peolpe who do it to do a dynamic balance. A dynamic balance means putting weights on both sides of the wheel. A static balcance puts the weights on the inside only. I did a static balance b/c I have aluminum wheels which can accumulate dirt and get discolored where the weight sits. It does not make a huge difference, but it you have stock wheels i recomend the dynamic balance. Make sure you tell them too, if they don't mention it they will most likely do a static balance.
I recomen that you do this first, not only is it needed in your situation, but it will eliminate one possible cause of the problem with minimal time and money.