What is a steering gearbox?
A steering gearbox is an integral part of your car’s power steering system. Its purpose is to translate the rotational movement of your steering wheel into the lateral movement of your front tires. The gearbox contains complex gear systems that amplify the driver’s input and transfer it to the tie rods, which move the wheels back and forth from side to side.
There are two types of steering gearboxes found in modern vehicles.
The most common type of gearbox found on most modern vehicles is a power steering rack and pinion. This system uses a pinion gear that rotates on a rack. As you turn the wheel, the pinion gear moves, causing the rack to move from side to side—this movement is then transferred to the tie rods, which connect to the steering knuckles and move the wheels.
The other type of gearbox is known as a recirculating ball system. This gearbox is used in the conventional power steering systems that are found in older cars as well as some modern off-road and heavy-duty vehicles. These gearboxes are much more complex than rack and pinion systems and use a worm gear and ball bearings to transfer the driver’s input to a Pitman arm.
When should I replace the steering gearbox on my car?
Steering gearboxes are generally designed to last for the lifetime of a car. That said, they can and do occasionally wear out over time. And you’ll need to replace yours when it shows signs of failure.
The most common signs of a bad steering gearbox include the following:
A very stiff steering wheel: One of the steering gear’s primary jobs is to make it easier to turn the steering wheel. When the gearbox begins to fail, it will lose that ability. If your steering wheel feels extremely stiff, it could be a sign of a failing gearbox.
Power steering fluid leaks: Many power steering system problems can cause a fluid leak. But once you begin leaking power steering fluid, you risk developing gearbox damage. While the leak may originate elsewhere, you should get a gearbox inspection if you notice red or reddish-brown puddles beneath your car.
Strange noises when steering: A bad gearbox may make grinding or clunking noises due to a lack of fluid or internal damage.
A burning oil smell: If your gearbox is bad and begins to overheat, you may notice a strong burning oil smell. If you notice this problem, stop your car immediately and call for help.
Keep in mind: The above issues can indicate other problems, like a bad power steering pump or a damaged steering column. The best way to accurately diagnose your car’s problem is to visit a certified mechanic for a steering system inspection.
How often should I replace my steering gearbox?
Steering gearboxes are designed to last for the lifetime of the vehicle. Because of that, there is no fixed replacement interval for them. But they are subject to wear and tear and can deteriorate over time.
You’ll only need to replace your steering gearbox if it fails. The top signs of a bad gearbox include overly stiff or loose steering, power steering fluid leaks, and grinding noises while turning the wheel.
Can I replace my steering gearbox myself?
A steering gearbox replacement is a fairly high-level repair job. And it’s probably too complex for most automotive novices and even intermediate home mechanics.
If you’re an experienced hobbyist and have access to a variety of tools, you can probably manage to get the job done. But if you’re uncomfortable working with the power steering system or don’t have access to the proper tools, you should absolutely contact a professional mechanic.