Car steering racks
Car Power Steering Racks
Car power steering racks are used in most modern cars. It is rack and pinion steering with power assistance.
Rack & Pinion Steering Rack - this is the man central part and consist of a long cyndrical tube. Inside the tube is a metal bar with teeth cut into the top of it. On one side of it (right hand side in AU) is a gear that engages with this row of teeth. The steering wheel is attached to this gear via various rods or linkages. Some cars run a fly by wire steering system, where there is no physical connection.
As the steering wheel rotates left and right the gear causes the toothed bar to move left and right in unison with the steering wheel. It is a very simple, accurate and effective form of steering. It is this rack that is power assisted through valving in rack body that makes steering easier. Both power steering hoses from the pump connect to the rack. As the rack goes left or right, hydraulic pressure from the pump assists the effort required to move it.
Steering Rack Ends - Steering rack ends are connected at each end of the toothed bar and move left or right with the bar. They have tie rod ends screwed in at their outer ends which connect the rack to the front suspension upright or hub. Where they connect to the rack they have a ball joint or pivot much like your shoulder socket. It allows the outer end of the rack end to go up and down with the suspension, while holding it securely onto the steering rack.
This is required as the steering rack is normally bolted to the vehicle body and can't move. So as the steering wheels turns to the right, it pulls the right hand side rack end and its tie rod end to the left, turning the right hand front wheel to the right. The opposite happens on the left hand side where it pushes the left hand side rack end and its tie rod end to the left, turning the left hand wheel to the right. Confusing but it depends on where the steering rack is mounted. Behind or in front of the front suspension centreline.
Steering Rack Boots - The steering rack boots are found at the ends of the steering rack and cover the steering rack ends on both sides. They are a concertina rubber boot designed to protect the end of the steering rack and the steering rack end ball joint or pivot from water, dust, dirt and road grime. Without them, the rack ends would wear out very quickly.
Popular Questions Asked
What are the problems you can have with a Steering Rack?
Apart from accident damage they are robust pieces of design. Like any item with moving parts, they will not last forever. Being powered the seals are the main item that fail. If the rack boot is split or torn, then contaminants can get in and may cause some damage. Probably to the seals.
Contaminated power steering fluid can also damage the rack. Any leak from the rack needs to be checked and repaired as it will only get worse over time.
Steering racks can develop a rattle or vibration and the steering can feel loose or vague. It will even a clunk as it gets worse.
What are the problems you can have with a steering Rack End?
Worn out or torn boots if not checked will cause the ball joint to wear prematurely. They will eventually wear out though this will speed up the process. A worn rack end will develop similar symptoms to a steering rack.
What are the problems you can have with a Steering Rack Boot?
Pretty easy and straight forward. If one is torn, damaged or split and can let contaminants into the rack end, simply replace it.