Solid bushings replace OEM parts for increased steering response and they outperform / outlast urethane often at a lower cost too. This CNC machined, CAD modeled 4pc anodized aluminum set fits perfectly after removing OEM bushings/sleeves due to 3d laser scanning and probing of the OEM subframe and diff. These come with the rack-forward crossmember center section, sold separately, but they can also be installed by themselves without any other parts. No press is required. DIY install can be done with a mallet at room temp or you may freeze them for 30 minutes ahead of time to make the process very easy. Grinding is required on the OEM lock ring as seen in the install PDF documentation.