The steering gearbox contains the gears that translate your steering inputs into direction, and multiply the driver’s steering changes so that the front wheels move more than the steering wheel. Most vehicles use a rack-and-pinion system, in which the steering wheel turns a pinion gear that moves on a rack to turn the front wheels.
Although steering gearboxes often last for the lifetime of the vehicle, it is possible for them to develop leaks or cracks. Some signs that your steering gearbox needs to be repaired or replaced are increased or jerky steering and the steering becoming loose and showing excessive play.
For most vehicles, the power steering system will last well over 100,000 miles before any failures occur. Mechanical failures and leaks in the power steering system are usually avoidable if maintenance has been performed according to the manufacturer’s service intervals. Keeping the power steering fluid fresh and the system free of contaminants is the key to ensuring long power steering system life. As any system that carries high pressure will, the system will eventually fail from normal wear and tear, but this should be well into the serviceable life of the vehicle.
Since most power steering issues will generate the same symptoms, it would be difficult to diagnose only one part, without understand the condition of the whole system. When symptoms emerge, the power steering fluid is inspected and topped off, and the condition and tension of the belt is noted. The system may need to be bled of air prior to diagnosis. Any leaks will then become very obvious, and mechanical failure of the power steering pump will be evident from noise or a pressure gauge inserted into the power steering line. Any dust boots and seals will be inspected for leaks. The rack and pinion gear set will be inspected for sounds typical of mechanical failure, and the input and output shafts will be examined for play.
Power steering gearbox leaks and mechanical issues are evident as soon as you move your vehicle, and power steering fluid on the ground is accompanied by strange noises and a different steering feel. Besides leaking oil, the power steering pump might sound overworked when turning normally as the malfunctioning steering gearbox begins to increase required input pressure before turning the wheels. Lastly, the steering gear may make a clunking noise, and the steering wheel may feel loose. When the mounting bolts break or stretch, the steering gear will be permitted to move back and forth, which will also create noticeable wear marks on the mounting area.
Power steering component failure almost always means a leak, but the amount of leaking fluid will determine if the vehicle can be driven. If failure of the pulley or accessory belt occurs, the vehicle may be stranded if the belt also drives other accessories. Small leaks will not prevent the vehicle from driving, but when fluid cannot be added quickly enough to keep the pump full, a tow truck is recommended to avoid damaging the fuel pump and steering gear.
Steering gearboxes can take some experience to position, install, and adjust. While not impossible to do at home, this is a repair that most people would need to go to the shop for. If you are experiencing any problems with your power steering system or steering gearbox, bring your vehicle in to your Certified Auto Repair Specialist of Pasadena today.