[Jdub]

Did you fully compress the shock prior to installing it to resaturate the seals? This is in the directions, along with advice to store the shocks upright. I wonder about these details though...

Check also the part numbers on each shock at the bottom to be sure they are identical.

Could be the car was being artificially leveled with one bad (old) shock that you have now replaced. I would complete any other susp. bits you plan on tending to and get an align/corner balance performed on the car.

John