The design of SSME, as well as any engines and rockets, are designed to meet the ground transportation loads. In addition, there are ground support equipment (GSE) to hold the engines in place and minimize those loads. So it is largely not a concern as far as its wear on the engine. <br /><br />The engine has been historically assembled in Rocketdyne's facility in Canoga Park, California, with many key manufacturing processes at the same location as well. Recently there's a move to take all production work out of California, mainly due to the increasing stringent environmental regulations here, as well as reducing labor cost (different 'market rate' between California and Florida/ Mississipi). <br /><br />Another factor is customer-driven, e.g., NASA in this case, who wants to have more control closer to its locations. Afterall, the orbiter maintenance & repair is being done in the OPF, and the SRB is stacked in the VAB, so why shouldn't the SSME be assembled & checked out at KSC as well? <div class="Discussion_UserSignature"> </div>