Steering racks fail in two distinct ways depending on their assistance type: hydraulic racks leak past their seals, and electric racks develop electronic faults and knocking from worn plastic bushings. Both can usually be repaired with individual components instead of a complete rack, which is what FEBEST supplies. Here is what to look for and what to do about it.
Summer is holiday season and long drives. If your car is what makes that free time work, the steering is worth attention while you are preparing. Here we look at the most common type, the steering rack, and what deserves a closer look.
How does a steering rack work?
A rack and pinion system consists of the rack itself, a toothed bar that slides left and right inside its housing. The driver turns the wheel, and that rotation, through the steering shaft and pinion gear, moves the rack, which turns the wheels through the tie rods.
If the wheels are heavy, driver effort alone will not be enough to turn them, so a hydraulic power steering system (HPS) or an electric power steering system (EPS) helps move the rack. Assistance is now effectively standard, and simple unassisted racks are gradually disappearing.
What goes wrong with hydraulic racks?
The hydraulics are the main problem with hydraulically assisted racks, and more precisely, loss of sealing.
When hydraulic fluid leaks out, air enters the system, and the more air there is, the less effective the assistance becomes, up to complete failure. Fluid loss also threatens the power steering pump, which relies on that fluid for lubrication and cooling.
In most cases the leak occurs past the rack seals. Either the upper seal, located where the steering shaft enters the rack’s control valve, or the side seals. Replacing rack oil seals is the standard repair, and the leak usually shows first as fluid weeping down the boot on one side.
In addition, on a high-kilometre rack the leak may be caused by wear on the rack bar itself, which means that even a new seal no longer sits fully against its surface. That is the point where a repair kit stops being the answer and the bar or the complete unit needs assessment.
What goes wrong with electric racks?
An electrically assisted system avoids the hydraulic problems, but it is not perfect either.
Here the electronics can cause trouble. The weak point is the steering position sensor, also called the steering angle sensor. It can fail outright, in which case a warning appears on the instrument cluster, or it can simply send incorrect data, in which case the EPS starts behaving incorrectly. Faults in the wiring to the assistance motor can add problems of their own.
The other weak point of electric racks is mechanical wear, play and knocking. The weakest link here is the plastic rack bushings.
Play in the bushings leads to accelerated wear of the rack bar and the drive pinion, because the correct clearance between them is lost. Driving in that condition for a long period risks dangerous consequences, up to complete loss of steering. Worn steering rack bushings also produce the knock over bumps that owners often misdiagnose as a suspension fault.
How can FEBEST help?
Our range includes a series of components intended for repairing steering racks, both hydraulic and electric. We supply parts for the targeted repair of the weak points described above.
1. Rack repair kits. These sets include everything normally required to repair the assembly. The specific contents are selected for each rack based on service experience. The kit for the Honda CR-V, part number 391-CRV, contains seals, sealing rings and metal washers, precisely the items for which accelerated wear data has been accumulated.
2. Rack seals. Sealing components made for the specific dimensions and design features of each rack. That removes the need to select a universal seal of doubtful suitability, which is where most botched rack repairs begin.
3. Bushings, mounting bushes and spacers. These are the components that secure the rack to the body or subframe. We supply parts for both electric and hydraulic racks, matching the material and geometry of the original exactly, which makes knocking and play easy to eliminate.
4. Steering rack gaskets. Another type of seal, protecting both against leakage from the rack and against dirt and water getting inside. A small, inexpensive, but essential repair component, and unlike seals it cannot be substituted with a universal alternative, because the dimensions are unique to each rack design. Inspect the steering rack boots at the same time, since a split boot is how the grit and water get in to begin with, and on gravel roads that happens quickly.
As a rule, most of these items do not exist as separate original parts, so FEBEST offers an excellent alternative here. Where the vehicle manufacturer allows only complete rack replacement, which today is extremely expensive, we offer intelligent repair solutions. The rack itself stays original, which adds to the reliability of the assembly. Many of the sealing rings used in these repairs are made to rack-specific dimensions for the same reason.
How do you extend the life of a repaired rack?
For the rack to work properly for a long time after a repair, several points during normal use are worth attention.
For hydraulic racks: keep an eye on the fluid level in the reservoir, and at every service inspect the hoses, the power steering pump and the rack for leaks. Unfortunately most owners only find out about a leak when the pump starts making its death rattle.
For electric racks: try to avoid prolonged aggressive steering input in extreme heat. Passenger car EPS units are not designed for a rally driving style and, in extreme conditions, are prone to overheating and potential shutdown. In a 40 °C Australian summer, repeated full-lock manoeuvring while reversing a trailer is enough to trigger a temporary reduction in assistance on some vehicles.
Another important point with EPS: avoid significant voltage drops in the vehicle’s electrical system, which means not driving with a faulty alternator or a flat battery.
The condition of the rack, and especially its assistance system, deserves careful attention. For an unprepared driver, particularly one without physical strength, a sudden loss of assistance while driving, which is the most common way it fails, can mean complete inability to control the car and a potential accident.
Safety note: steering is a safety-critical system. Torque every fastener to the manufacturer’s specification, and have a wheel alignment performed after any rack, tie rod or bushing work. Excess steering play and fluid leaks are both inspection failures at a state roadworthy check or a New Zealand Warrant of Fitness, so do not defer either. If assistance fails while driving, the steering still works but requires far more effort, so slow down progressively rather than braking hard.
Frequently asked questions
What are the symptoms of a failing steering rack?
Fluid weeping from the boots or the rack housing, a knock over bumps that changes when you hold the wheel, vague or wandering steering on centre, and a groan from the pump on lock. On an electric rack, a warning light or assistance that comes and goes points at the sensor or wiring rather than the mechanicals.
Can a leaking steering rack be repaired, or does it need replacing?
It can usually be repaired. Rack seals, sealing rings and gaskets are available as individual components, so a leaking rack does not automatically mean a complete unit. Replacement becomes the right call only when the rack bar itself is scored or worn, since a new seal will not hold against a damaged surface.
Why does my steering knock over bumps?
Worn rack mounting bushings are the most common cause, followed by worn tie rod ends and ball joints. The rack test is simple: have someone rock the steering wheel slightly while you watch the rack housing for movement against its mounts. Movement there means the bushings, not the suspension.
Is it safe to drive with the power steering warning light on?
Only as far as necessary to get the car checked. The steering still functions mechanically, but assistance may cut out without warning, and low-speed manoeuvring becomes very heavy. Check the fluid level on a hydraulic system and the battery and alternator on an electric one, since low voltage alone can trigger the fault.
How often should the power steering fluid be checked?
At every service, and immediately if the steering groans or feels heavier than usual. Use only the fluid specification listed by the vehicle manufacturer, since the wrong fluid attacks the seals. A level that keeps dropping means a leak that needs finding, not topping up.
Do tie rods need replacing at the same time as rack work?
Not automatically, but check them while the car is on stands. If a tie rod end has play or a torn boot, replacing it during the same job saves a second alignment. Any component that contributes to steering play is worth addressing while the geometry is being reset anyway.
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