What can cause
a rack and pinion system to leak?

Most of the cars on the road today use a rack and pinion steering system with power steering. The power steering makes it easier to steer, but adds complexity to the compact rack and pinion system, which can make it more difficult (and expensive) to repair.

Adding power steering to a rack and pinion steering system changes the design slightly. A cylinder with a piston is put in the rack, and fluid is added to both sides of the piston. Adding pressure to the fluid on one side of the piston forces the piston to move, turning the rack and assisting with steering.

What causes a rack and pinion system with power steering to leak?

Over time, components in the rack and pinion steering system can start to wear out as they are frequently used when driving and steering. This can result in loose fittings.

While your power steering system could start to leak at the connection points or through cracks in the flexible rubber hoses and lines, it is more likely that it will start to leak from one of the seals on your rack and pinion. Environmental conditions and driving styles can cause your seals to dry out, shrink, crack or become unseated.

There are three main factors that can cause leaks: 

• The hoses and lines are made from a flexible rubber that can crack;
• The connections can loosen;
• The seals between the steering column and the rack and pinion or around the tie rod connections can shrink, crack, dry out or become unseated.

It’s worth mentioning that the leak is coming from your power steering system, not your rack and pinion system. That’s because the steering rack is lubricated with grease.

How can you tell if a rack and pinion system with power steering is leaking?

Leaking steering fluid typically has a burning oil smell and is usually red or pink in colour. You might notice a small puddle of this on the ground under the rear of your motor.

Alternatively, if you have a jack, jack stands or a ramp, you can check your rack and pinion system directly for leaks. Once you are under your car, it is relatively easy to check the hoses, connections and seals.

Is it safe to drive your car if a rack and pinion system with power steering is leaking?

When the leak first starts, your steering will start to become difficult and inconsistent until it fails completely as all power assistance is lost. If this happens when you’re driving on a relatively straight road, it won’t make much difference. However, if you need to turn, especially if you are going at speed, it will not be easy or safe. It is worth noting that while a leaking system won’t directly cause a crash, it can contribute to an incident if the driver lacks sufficient strength to handle the heavy steering.

Additionally, your leaking power steering system can quickly cause severe consequences. For example, causing the steering rack or steering gear-box to overheat.

Repair options for a leaking rack and pinion system with power steering 

Rack and pinion leaks are often expensive to fix as the seals are difficult to service, even by a mechanic. Most leaks are solved by replacing the entire rack and pinion system to ensure the system works correctly.

An alternative is a “power steering stop leak” product. While these might look like a good solution, they are only a temporary fix and will remain in your power steering system until your next power steering flush. 

Want to know more?

Interested in finding out more about how to maintain and repair your car? Visit MOOG TV and explore useful videos, straightforward installation guides and expert tips. 

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