Power steering on Nissan Murano the second generation (Z51 body) is a complex hydraulic system that makes it easy to control a heavy crossover. The heart of this system is power steering pump, which creates the necessary pressure for the steering mechanism to operate. If this unit fails, the driver is faced with a sharp deterioration in controllability and an increase in effort on the steering wheel, which makes the operation of the car unsafe.
Many owners Nissan Murano Z51 It is a mistaken belief that a pump malfunction only manifests itself in the form of noise, but the problem may be hidden in a gradual loss of performance. If you notice that the steering wheel has become heavier when turning or a hum has appeared when you turn the steering wheel all the way, this is a signal that urgent diagnostics are needed. Timely intervention allows you to avoid expensive repairs to the steering rack, which also suffers from poor-quality pump operation.
Design features and operating principle
Power steering pump Nissan Murano Z51 is a plate-type unit driven by a belt drive from the engine crankshaft. Its job is to create a constant flow of high-pressure hydraulic fluid, which is then directed to the steering rack. The design of the pump involves the use of special sealing rings and bearings designed for high speeds and temperature loads.
It is important to understand that the efficiency of the entire system depends on the tightness and purity of the working fluid. Any leakage or dirt entering the pump housing can lead to rapid wear of the operating elements. Hydraulic pressure in the Z51 system reaches significant values, so even microscopic defects can cause serious damage.
A special feature of this unit is the presence of a built-in pressure relief valve, which protects the system from surges during sharp turns of the steering wheel. If this valve is stuck, you may experience a pulsating steering wheel or excessive noise from the pump. Regular check oil level in the expansion tank is a mandatory procedure to extend the life of the unit.
Pump fault diagnosis
You can identify a problem with the power steering pump by a number of characteristic symptoms that become noticeable even during a cursory inspection of the car. The most obvious sign is the appearance of a hum or whistle when turning the steering wheel, especially at low speeds or in a static position. The sound often changes with steering angle and engine speed, indicating problems with the bearings or impeller blades.
In addition to noise, pay attention to the behavior of the steering wheel. If he became spin tight or requires significant effort to maneuver, this is a sure sign of loss of pump performance. In some cases, the steering wheel may jerk or jerk, which indicates air in the system or wear of internal components.
- 🔊 The appearance of a hum, whistle or squeak when turning the steering wheel in any direction.
- 🚗 Increased effort on the steering wheel, especially in winter or at low speeds.
- 🛢️ Power steering fluid leaks from under pump seals or high pressure hoses.
- 💧 The presence of foam or air bubbles in the expansion tank with liquid.
For accurate diagnosis, it is necessary to use a pressure gauge connected to the system. This will allow you to measure the actual pressure created by the pump and compare it with factory standards. If the pressure does not correspond to the values specified in the documentation for Nissan Murano Z51, the unit requires replacement or repair.
⚠️ Attention: Do not ignore the appearance of foam in the power steering reservoir. This is a sure sign of air in the system, which can lead to overheating of the pump and its complete failure within a few minutes of operation.
Selection of original and high-quality analogues
When choosing a new power steering pump for Nissan Murano Z51 Owners have a dilemma: install an original unit or save on a proven analogue. Original pump from Nissan (article numbers often start at 49000...) are guaranteed to fit all parameters, have perfect balancing and durable materials. However, its cost can be quite high, especially if you buy it from a dealer.
There are many analogue manufacturers on the market that offer products of acceptable quality. Among the most popular brands are Zexel, Komatsu and Denso, which often act as suppliers of components for the manufacturer. When choosing, it is important to pay attention to the quality of the casting of the case, the presence of markings and the production date.
You should not buy the cheapest Chinese fakes, since their service life often does not exceed 10-15 thousand kilometers. Such pumps may not withstand the loads typical of a crossover Murano, and quickly fail, damaging the steering rack. Original spare part or a high-quality analogue is an investment in safety and comfort.
- 🏭 Original Nissan - maximum reliability, but high price.
- 🛠️ High-quality analogue (Zexel, Denso) - good value for money.
- ⚠️ Cheap copies - the risk of rapid failure and breakdown of adjacent units.
- Original Nissan
- High-quality analogue (Zexel/Denso)
- Used from disassembly
- Cheap analogue
- I don't know yet
Step-by-step instructions for replacing the pump
Replacing the power steering pump with Nissan Murano Z51 is a labor-intensive procedure that requires a certain set of tools and skills. Before starting work, it is necessary to prepare the vehicle by placing it on a level surface and disconnecting the battery terminal to prevent accidental starting of the engine. You will need a jack, a set of sockets, a container to drain the fluid, and a new pump assembly.
First you need to drain the old hydraulic fluid. To do this, disconnect the return hose from the pump and direct it into a container. Crank the engine with the starter (without starting) or have an assistant turn the steering wheel to push out any remaining oil. Then remove the attachment drive belt by loosening the tensioner. This will provide access to the pump itself and its mountings.
☑️ Preparing to replace the power steering pump
Disconnect the high pressure and return hoses from the pump housing. Be prepared for some liquid to still leak out, so provide additional containers. Unscrew the bolts securing the pump to the bracket and carefully remove it. When installing a new unit, make sure that the O-rings are replaced with new ones and installed correctly.
After installing the new pump, it is necessary to fill the reservoir with fresh fluid. Run the engine for a few seconds, then stop and check the level. Repeat the procedure several times until the level stabilizes and the system is free of air. Be sure to check the pump for leaks and abnormal noise.
⚠️ Attention: Never start the engine with an empty power steering reservoir, even for a short time. This can instantly destroy the bearings and vanes of the new pump due to lack of lubrication.
What to do if you can’t remove the belt?
If the belt is too tight and does not give in, check the condition of the tension roller. It may be stuck or its spring has weakened. In this case, the tensioner pulley will need to be replaced before installing a new pump.
Bleeding the system and removing air
The process of bleeding the power steering system is a critical step after replacing the pump. Air trapped in hydraulics is compressible, unlike liquid, which leads to a loss of pressure and the appearance of a characteristic hum. To properly remove air, you need to turn the steering wheel all the way left and right several times with the engine running, but do not hold it in extreme positions for more than 3-5 seconds.
During pumping, constantly monitor the fluid level in the expansion tank. It may drop sharply as air leaves the system. If the level drops below the minimum, be sure to add fluid so as not to air the pump again. Air jams can only be removed if this procedure is carefully followed.
If the noise does not go away after several bleeding cycles, the system may still contain air. In such cases, it is recommended to raise the front of the car on a lift or jacks so that the wheels do not touch the ground, and repeat the procedure for turning the steering wheel. This will reduce the load on the steering mechanism and speed up the release of air.
Before starting pumping, check the tightness of all hose connections. Oil leakage during operation will create a new air flow into the system, nullifying all efforts.
Specifications and compatibility table
For the convenience of selecting spare parts and understanding the technical features of the power steering system Nissan Murano Z51 Here is a summary table of the data. These parameters are relevant for models with 3.5 liter petrol engines (VQ35DE). When choosing analogues, be sure to check these characteristics.
| Parameter | Meaning |
|---|---|
| Pump type | Plate, belt drive |
| Original article | 49000-ZZ00A / 49000-1AA0A |
| Liquid type | PSF (Power Steering Fluid) or ATF Dexron III |
| Working pressure | up to 100 bar (at load) |
| System capacity | about 1.1 liter |
Please note that the use of non-standard fluid may damage rubber seals and corrode metal parts. Power steering fluid must meet the specifications specified in the vehicle's service book. Mixing different types of oils is strictly prohibited.
⚠️ Attention: Using ATF fluid instead of specialized PSF is only permissible in extreme cases and should be temporarily replaced with original fluid at the earliest opportunity, as this may change the characteristics of the seals.
Prevention and service life extension
In order for the power steering pump to last as long as possible, it is necessary to follow simple operating rules and regular maintenance. The main rule is to monitor the cleanliness and level of fluid in the system. Dirt and metal shavings entering the oil act as an abrasive, destroying the internal walls of the pump and rack.
It is recommended to replace the power steering fluid every 60-80 thousand kilometers, even if visually it seems clean. Over time, the oil loses its lubricating properties and oxidizes. The condition of the drive belt and tension roller is also important, since belt slippage causes the pump to overheat.
- 🔄 Change power steering fluid regularly according to regulations.
- 🔍 Monitor the oil level and the absence of leaks.
- 🚫 Avoid holding the steering wheel in extreme positions for more than 5 seconds.
- 🛡️ Protect hoses from mechanical damage and high temperatures.
Regular fluid replacement and level monitoring are the easiest ways to extend the life of the power steering pump and avoid costly repairs to the steering rack.
Frequently asked questions (FAQ)
Is it possible to drive with a faulty power steering pump?
Driving is technically possible since the steering wheel still turns, but the effort will be very high. This is a safety hazard, especially in emergency situations, and can cause damage to the steering rack.
Why does the power steering pump make noise only at idle?
Most often, this indicates a low fluid level or air in the system. The reason may also be wear of the bearings, which begin to make noise at low pressure and speed.
What kind of fluid to pour into the power steering Nissan Murano Z51?
It is officially recommended to use liquid NISSAN Genuine Power Steering Fluid. It is possible to use high-quality analogues that meet the Dexron III specification, but it is better to stick to the original.
How much does it cost to replace a power steering pump?
The cost of work depends on the region and service, but usually it ranges from 5 to 10 thousand rubles, excluding the cost of spare parts. The pump itself is the most expensive part of the repair.
Is it possible to restore an old pump?
In some cases, repairs are possible by replacing oil seals and bearings, but this is only economically justified if you have a high-quality repair kit and experience. It is often easier to install a new or remanufactured unit.