Car rear suspension Nissan Primera P12 It is distinguished by a complex multi-link design, which provides excellent controllability, but creates specific problems during maintenance. One of the most common malfunctions is the failure of the wheel bearing, which is integrated directly into the steering knuckle. Ignoring the characteristic hum or play can lead to wheel jamming and complete loss of controllability at high speed.
Many owners are faced with a dilemma: change only the bearing or the entire fist assembly at once. In the case of Primera P12 It is often easier and more reliable to replace the assembly, since the old fastening bolts can become stuck, and pressing in a new bearing requires special tools. However, independent replacement is possible with a competent approach and the right set of tools.
This article will tell you in detail about the replacement procedure, design features of the rear suspension and typical mistakes that beginners make. We'll show you how to properly remove the caliper, unscrew the hub nut and install a new element so that your car can drive quietly and safely again.
Diagnosis of hub unit malfunction
It is possible to determine that the rear hub bearing has worn out by a number of indirect signs that appear at different speeds. The most obvious symptom is a growing hum, similar to the sound of a flying airplane, which changes its pitch depending on the speed of movement and the direction of the turn.
When driving in a straight line, the sound may be almost unnoticeable, but as soon as you turn the steering wheel a little, the load on the wheels is redistributed, and the hum intensifies or, conversely, subsides. In the case of Nissan Primera P12 A situation often arises when, when turning left, the load on the right wheel increases, and it is this wheel that begins to hum.
In addition to acoustic signals, it is necessary to check for play. Raise the car on a jack, rock the wheel with your hands in the vertical and horizontal planes. If you feel a knocking or play that is not eliminated by tightening the nut, this is a sure sign of destruction. wheel bearing or wear of suspension elements.
It is important to distinguish a wheel bearing from worn-out control arm bushings or ball joints. If the knocking noise is heard when driving over small bumps, and not at speed, the problem is most likely in the levers. However, if the bearing is severely worn, steering wheel wobble or brake disc vibration may occur.
Necessary tools and consumables
To carry out replacement work, you will need an impressive set of tools, since the unit is secured with powerful bolts, which are often subject to corrosion. Be sure to prepare 30 mm head for the hub nut and a powerful wrench, since the tightening torque is very high.
- 🔧 Set of sockets and ratchets (including extension and universal joint for access to knuckle bolts)
- 🔨 Hammer and punch for knocking out an old bearing or stabilizer link
- 🧴 WD-40 or penetrating lubricant for treating soured threaded connections
As for consumables, the main emphasis is on the part itself. It is recommended to buy the bearing assembled with an ABS ring, since the sensor is Primera P12 often breaks during dismantling. Also stock up on new caliper and steering knuckle mounting bolts, as old ones often break off when unscrewed.
Don't forget about the brake fluid, as some of it may leak out when the caliper is disconnected, as well as new brake pads if the old ones are worn out by more than 50%. Useful for cleaning parts brake cleaning spray and a wire brush.
⚠️ Attention: Never try to unscrew the hub nut without securing the wheel from turning. Use a pry bar or powerful tool through the brake rotor holes to avoid personal injury or damage to parts.
- Self-replacement of only the bearing
- Replacing the fist assembly
- Buying a used unit
- Purchasing an original Nissan unit
The process of dismantling the steering knuckle
Begin work by lifting the car and removing the wheel. Unscrew the two caliper mounting bolts located at the rear and hang it on a wire so as not to damage the brake hose. The brake disc is removed together with the knuckle if it is not stuck, but more often it will have to be unscrewed separately.
Next, you need to disconnect the stabilizer bar link and lower arm. Bolts securing the lever to the knuckle Primera P12 often have a conical shape and can stick. Use blast cleaning and heating with a burner, if they cannot be unscrewed with a key.
- 🔩 Unscrew the stabilizer link nut and remove your finger from the lever
- 🔩 Remove the ABS sensor from the steering knuckle by disconnecting the connector inside the passenger compartment or in the engine compartment
- 🔩 Unscrew the fastening bolts steering knuckle to swing arm and shock absorber
After all the fasteners are released, the fist can be removed. Be careful as it is heavy. If you are only replacing the bearing, you will have to press it out on a bench. If you are changing the fist assembly, simply move the levers and shock absorber to the new unit.
☑️ Preparation for dismantling
⚠️ Attention: When removing a brake hose or caliper, it is strictly forbidden to leave it hanging on the hose - this will lead to stretching of the rubber and breaking the tightness of the system.
Bearing replacement or complete knuckle replacement
If you decide to replace just the bearing, you will need a press or a heavy-duty puller. The old bearing is knocked out of the inner race, then the retaining ring is removed and the outer ring is removed. The new part is pressed strictly along the inner ring, otherwise the separator will collapse.
Many masters Nissan Primera P12 They prefer to change the steering knuckle assembly with the bearing already installed. This saves time and eliminates the risk of incorrect installation. However, the cost of such a unit is higher, and finding a high-quality analogue may take time.
When replacing the knuckle assembly, make sure that the seats for the levers are not worn out. If the mounting holes are broken, the new assembly will hang loose and play will occur again after a short time. In this case, replacement of the suspension arms is required.
The nuances of installing an ABS sensor
The ABS sensor on the P12 is very fragile. When removed from an old fist, it often breaks. If you are only replacing the bearing, carefully drill out the sensor or use special extractors to avoid damaging the wiring inside.
After installing a new element or assembling a fist, it is necessary to lubricate the seats and check the free movement. Make sure the retaining ring is installed correctly and is not misaligned. Errors at this stage lead to rapid destruction of the new part.
Replacing the fist assembly saves time and reduces the risk of errors during pressing, but requires more financial costs to purchase the unit.
Assembly and tightening adjustment
Assembly is carried out in reverse order. Pay special attention to tightening the bolts securing the steering knuckle to the arms. The tightening torque must be strict, but not exceed the permissible values, so as not to strip the threads in the aluminum levers.
The hub nut is tightened with enormous force. After installing the wheel and lowering the car to the ground, be sure to check the tightening torque. If the nut is overtightened, the bearing will overheat and fail. If it is not tightened, there will be a backlash.
| Detail | Tightening torque (Nm) | Features |
|---|---|---|
| Hub nut | 180-200 | Fixation with a cotter pin or a new nut is required. |
| Knuckle bolts | 100-110 | Use thread locker |
| Caliper bolts | 45-50 | Check the condition of the guides |
| Stabilizer link | 20-25 | Tighten with loaded suspension |
Be sure to connect the ABS sensor connector and check that the wire does not rub against rotating parts or the body. After completing the work, be sure to carry out a wheel alignment, since interfering with the suspension geometry will inevitably change the wheel alignment angles.
Typical maintenance errors
One of the most common mistakes is ignoring the condition of the silent blocks of the levers. When replacing a bearing, it is often discovered that the suspension arms are critically worn. Installing a new bearing on worn arms will cause rapid failure.
Another common mistake is trying to use a hammer to press a bearing without a mandrel. Impacts on the outer ring destroy the cage, and the bearing fails after several thousand kilometers. Use only mandrels, suitable in diameter.
- ❌ Don't use old bolts with broken threads or corrosion
- ❌ Do not tighten the nuts suspended, when the wheel hangs in the air
- ❌ Don't ignore the ABS sensor during assembly
Also, any deviation from the factory parameters can lead to the vehicle pulling to the side or uneven tire wear. Therefore, work must be performed with high precision.
FAQ: Frequently asked questions
Is it possible to drive with a faulty rear bearing?
Short term - yes, but it is dangerous. If the wear is severe, the bearing may seize, causing the wheel to lock and loss of control, especially when turning or braking.
How long does it take to replace a bearing?
For an experienced technician, replacing one wheel takes about 1.5–2 hours. If you change the fist assembly, the process may take less time, since pressing out is not required.
Do I need to do a wheel alignment after replacement?
Yes, definitely. Any intervention in the suspension elements that affect the wheel alignment angles requires adjustment. On the P12, the rear suspension is adjustable, and the settings may change.
Which bearing is better to choose: original or analogue?
Original bearings Nissan They last longer, but are expensive. High-quality analogues (for example, Koyo, SNS) are an excellent alternative and are often installed on the conveyor.
How can you tell if the problem is with the bearing and not with the brakes?
The sound of worn brakes is a grinding or squealing sound that is heard when you press the pedal. The bearing noise is constantly heard when driving and changes when turning, regardless of braking.
⚠️ Attention: Replacing a bearing on the rear axle of a Nissan Primera P12 requires mandatory adjustment of the wheel alignment angles, since the design of the rear suspension directly affects the camber. Ignoring this requirement will lead to rapid tire wear.