The steering rack is vital to every vehicle on today's roads, as without them your vehicle simply wouldn't negotiate corners. There are three types of steering rack; these are Manual, Power and Electric.
The manual racks are mostly found on earlier vehicles and tend to be heavy when turning corners. This also makes doing simple tasks such as parking and 3-point turns quite tiring if you are used to driving vehicles with power steering. Power steering was introduced to the market to aid drivers, making the steering feel nice and light, and easier to operate. Power steering is now a standard feature on most of the vehicles you can currently buy. It works by circulating hydraulic fluid through the PAS Pump and around the steering rack, the internal of the pump has variable vanes which allows the pump to vary the level of assistance it gives. As technology advances the conventional hydraulic driven power steering system is being replaced with a simplified electric unit. This allows for greater accuracy and variable assistance given to the driver.
Fitted to the end of the steering racks are 'Rack Boots' these are used to keep the joints where the steering tie rod ends join the rack surrounded in grease.