Could be a number of things..
*Check your hinge pins, sometimes one is slightly bent and will cause the lower arm to lock in one spot.
*Check shock mountings, too tight will cause the same problem.
*Check the driveshafts, they could be binding.
*O Rings in the outdrive cups as per instructions?
*Bearing not seated correctly in the front upright.
There's a few things to start off with anyway.