Bolt on solid bushings replace old worn out OEM parts that wont let you get the power to the ground, and they outperform / outlast urethane too. This CNC machined, CAD modeled 6pc anodized aluminum set fits perfectly due to 3d laser scanning and probing of the OEM subframe and diff. these are great to install at the same time as the sub frame risers, sold separately. Some people with older cars actually get less noise from the drivetrain because they didn't realize just how bad the original bushings had become despite solid mounts naturally transmitting more noise than rubber. The gallery shows the correct installation orientation of each piece. Click the red PDF link for install documentation.