How Steering Parts Fail After Fluid Leaks
Even a small leak in power steering fluid can cause lots of damage before it becomes apparent how serious the problem is.
The Pump Runs Dry First
Fluid lubricates the pump’s bearings and keeps the vanes cool. Without an adequate supply, the bearings and vanes are subjected to excessive wear due to heat. You may hear a whining noise that could indicate a low fluid condition in the power steering system.
The Rack Bore Gets Scored
Steering fluid also lubricates the rack and piston. If the fluid level becomes critically low then the piston can score the bore of the rack. The scoring of the bore means that the rack cannot hold pressure equally across all points, and therefore the steering will become loose or pull to one side when steering.
Seals Harden and Crack
The power steering seals are designed to be flexible and grip the steering rack piston whilst submerged in fluid. As the fluid level drops the seals are slowly dried out. As they harden they will begin to crack allowing pressure to escape. This will make the original leak worse, and can create new leaks elsewhere in the system.
Replacing Steering Parts Correctly
By the time your local repair shop gets to repair your steering it is usually too late and other parts have been damaged also. Replacing steering parts 1 at a time and expecting them to perform properly when the other nearby parts have been damaged is common but usually does not work out well for you. Replacing all parts that were damaged in addition to the part that failed and then flushing the entire system is the better option.
When handling and/or disposing of power steering fluid that has leaked from a vehicle, refer to the safe handling of hydraulic fluids information for guidance on skin contact precautions and proper disposal.
Catching a small leak early will save you money against the cost of repairing the damage to the associated components that a dry system can cause.
