OEM sway bars are designed and manufactured by the Original Equipment Manufacturer (OEM) of the vehicle. These bars are generally designed to meet the standards of the vehicle at the time of production but may not provide the highest level of performance or stability.
Custom sway bars are designed and manufactured by a third party or aftermarket supplier. These bars are designed to provide higher levels of performance and stability than the OEM bars and may be adjustable to suit the owner's particular needs. Custom sway bars may offer more options for tuning the suspension, allowing for improved handling characteristics.