Any car owner Skoda Octavia A5 over time, it encounters a characteristic hum, intensifying with turns and speed. This sound often signals that front wheel bearing It is out of order and needs immediate replacement. Ignoring the problem can lead to a wheel jamming, breaking the swivel fist, and even losing control at high speed.
The repair process on the PQ35 platform, which is used by this model, has its own characteristics. You will need not only a specialized tool, but also knowledge of the intricacies of tightening threaded connections. Unlike many other cars, it often requires use. drifts and hydraulic press, or specific removers, so as not to damage the suspension details.
Diagnosis of faults and selection of spare parts
Before starting the disassembly, you need to be sure exactly about the cause of the noise. Often, the hum of the bearing takes a malfunction. CV joint Or broken lever silentices. Conduct the test: accelerate to 60-80 km / h on an empty stretch of road and smoothly turn the steering wheel left and right. If the noise is increased when you turn right, then the problem is in the left wheel, and vice versa.
When choosing a new part, it is critically important to pay attention to the presence of a built-in sensor. Abs. On Skoda Octavia A5 a bearing with a magnetic ring and a sensor wire is used, the length of which must strictly correspond to the factory parameters. Buying a non-original part without checking the length of the wire will lead to errors on the dashboard and inoperability of security systems.
The parts market offers many options, but for reliability it is better to choose proven manufacturers. Here are the main brands that have proven themselves on the VW Group platform:
- π§ SKF - standard of quality, often supplied to the conveyor, has excellent lubrication.
- βοΈ FAG German production, high wear resistance, ideal geometry.
- π‘οΈ Timken - reliable bearings, resistant to high loads and dirt.
Do not save on this detail, as the cost of replacing work in the service often exceeds the price of the spare part itself. Savings on the brand can lead to the fact that after a couple of thousand kilometers you will have to disassemble the suspension again. Skoda Octavia A5 It is famous for its hardy suspension, but only if high-quality components are used.
Necessary tools and vehicle preparation
To carry out the work, you will need an impressive set of tools, since the node is tightly attached and requires considerable effort to dismantle. Be sure to prepare a jack, reliable stands and a full set of heads, including 13, 16, 18, 21 and 30 mm. Pay special attention to the key for wheel bolts and the stop rings removable.
The most difficult element in this process is knocking out the old bearing and pressing the new one. You'll need it. special puller Or a hydraulic press. If you work in a garage, you can do without a press using a long pipe and a powerful percussion tool, but the risk of damaging the swivel fist increases many times over.
You will also need a dynamometer key to tighten your critical nodes properly. An untied nut of the hub can lead to a rapid failure of a new part, and a twisted one - to the failure of the thread. Do not forget about the WD-40 aerosol lubricant or similar for unscrewing the boiling bolts of the brake caliper and levers.
It is important to prepare the workplace: the car should stand on a flat surface, and the wheels remaining on the ground should be securely locked. If you change the bearing only on one side, be sure to remove the protective covers from the levers on the opposite side so as not to damage them when working.
- π οΈ Dynamometer key (range 100-250 Nm).
- π¨ Metallic squirt and a set of percussion heads.
- 𧴠Lubrication for slithers and threaded joints.
Step-by-step instructions for dismantling the unit
Start by loosening the hub nut on an unraised car. This nut has a left or right thread depending on the side, and the tightening moment there reaches 250 Nm, so you can not do without a powerful lever and impacts. After that, lift the car, install it on the stand and completely remove the wheel.
The brake caliper must be removed. Unscrew two guide bolts on 13 mm And hang the caliper on the wire so that the brake hose doesn't damage. Remove the brake disc, previously unscrewing the fixing screw on 5 mm (starring) Now you have access to the hub and bearing.
The next step is to disconnect the ABS sensor. Be extremely careful as the sensor wire is very fragile and easily breaks. Disconnect the connector and unscrew the sensor itself, which often clings to the landing place. Use penetrating lubricant, but do not use brute force to avoid breaking the sensitive element.
Now we need to release the turning fist. Unscrew the ball support mount bolts to the swivel fist and remove the ball finger from the hole. If the bolts do not unscrew, use a hammer, gently tapping the joint place. You will also need to unscrew the nut of attaching the lever to the fist.
After all the mounts are unscrewed, you can remove the hub along with the inner ring of the bearing. If the inner ring is left on the shaft of the ShRUS, it will have to be knocked out. The inner ring of the bearing always remains on the hub during dismantling, unless it has been previously removed.. This is critically important to remember so as not to damage the landing site.
To remove the bearing from the swivel fist, use a removable or press. It must be knocked out strictly from the outside, relying on the interior ring of the tenant. Do not press on the outer ring, as this can damage the separator and ball mechanism.
- Complete set of pullers
- Just a jack and keys
- I'm planning to contact the service
- There's only press.
New bearing installation and assembly
Before installing a new part, carefully clean the seat in the swivel fist from rust and dirt. Use a file or sandpaper to achieve a perfectly smooth surface. Any irregularity can lead to a warping of the bearing and its rapid destruction.
Pressing the new bearing is necessary with the help of a mandrel, which rests on the outer ring. This ensures an even distribution of effort. If you use a press, monitor the process visually so that the part enters strictly perpendicular. Blows on bearings with a hammer are strictly prohibited.
After installing the bearing in the fist, it is necessary to install the hub. If the inner ring is left on the old bearing, it must be knocked off the hub using a mandrel resting on the inner ring. Then put the hub on the new bearing and press it to the point.
The assembly is carried out in reverse order. Pay special attention to tightening the bolts of fastening the ball support and levers. Use the dynamometer key and check the table of the moments of tightening. Donβt forget to install a new lock bolt if the old one has been deformed.
The final stage is the tightening of the nut of the hub. This operation requires considerable effort and should be performed with the car lowered when the load on the suspension is maximum. After tightening, be sure to check the backlash of the wheel, swaying it with your hands.
- β Check the length of the ABS sensor wire before installation.
- β Clear the seat from corrosion.
- β Use new locking elements and bolts.
- β Check the time of tightening of all connections.
βοΈ Suspension assembly
Moments of puffing and technical nuances
Proper tightening of threaded connections is the key to the durability of repair. Nana Skoda Octavia A5 Different types of threads and bolts are used with different tightening moments. Errors in this point can lead to unscrewing parts on the go or their destruction from vibration.
Pay special attention to the nut of the hub. It must be tightened with the force specified by the manufacturer and crumpled into the groove. After tightening, be sure to check the work of the brakes and the absence of backlashes. If the nut is tightened too weakly, the hub will begin to luft and quickly fail.
Below is a table with the main tightening moments for the front suspension node:
| element | Tightening torque (Nm) | Note |
|---|---|---|
| Hub nut | 250 + 90Β° finish | New nut, tighten on the ground |
| Caliper bolts | 30 + 90Β° | Use a torque wrench |
| Ball-support bolt | 70 + 90Β° | Bolt replacement is required |
| The nut of the lever | 50 + 90Β° | Check the status of the Bushings. |
| Wheel bolts | 120 | Cross tightening pattern |
Remember that many bolts on the VW platform have a plastic insert or a special coating that works as a thread fixer. Reuse of such bolts without applying the fixator is unacceptable. If you use old bolts, make sure the thread is in excellent condition and has no trace of damage.
What to do if the hub nut does not unscrew?
Use a shock screw or long tube. You can warm the nut with a blowtorch, but be careful with brake fluid. Sometimes the "unwind-twisting" method using penetrating lubricant helps.
β οΈ Warning: Never attempt to knock out a bearing by leaning on the inner ring. This will destroy the separator and make the part unusable. Always press on the outer ring when pressed and on the inner ring when knocked out.
Work inspection and descent-disruption
After all the work is completed, be sure to check the brake system. Press the brake pedal several times to keep the pads in place. Make sure there are no jamming and extraneous sounds when scrolling the wheel. The brake disc shall rotate freely without friction on the caliper.
The most important step after replacing the hub bearing is to check the angle of installation of the wheels. Replacement of suspension units inevitably changes the geometry, so without a visit to the stand, the operation of the car is impossible. This will ensure uniform tire wear and proper vehicle behaviour on the road.
It is also recommended to conduct a computer diagnostics. Connect the scanner and check for no errors in the ABS system. If the sensor is damaged or poorly connected, the error may remain in memory and burn on the dashboard. Clear the errors and conduct a test trip.
For the first 100-200 kilometers after replacement, watch for the sound from the suspension. If a new hum or knock appears, stop immediately and check for a puff of all connections. Sometimes there is a mistake made during the assembly, which can be easily corrected at an early stage.
Before going to the stand descent-dump warm up the engine and suspension, having traveled a couple of kilometers. Cold rubber and suspension can give distorted results of measuring the angles of the wheel installation.
Typical replacement mistakes
Many car owners make the mistake of trying to save money on the tool. Attempting to knock out the bearing with a hammer without a mandrel often leads to deformation of the swivel fist. As a result, you will have to change not only the bearing, but also the entire fist, which will significantly increase the cost of repair.
Another common mistake is to ignore the state of the ABS sensor. If the sensor wire is damaged, the ABS system will stop working and the corresponding lamp will light up on the dashboard. Replacing a sensor assembly is often cheaper than trying to repair a wire.
Sometimes masters forget to replace lock bolts, which are disposable. Their reuse can lead to self-unwinding during operation. Always check the condition of the bolts and change them to new ones if necessary.
Properly pressing the bearing and observing the tightening moments is 90% of the success of the repair. Do not skimp on the tool and do not miss the descent-fall stage.
β οΈ Note: It is forbidden to use old locking nuts of the hub. They have a plastic insert that loses its properties after the first dismantling. Make sure to use a new nut every time you replace the bearing.
How do I know if the bearing is worn out?
The main feature is a hum, which is amplified when turning the steering wheel in the opposite direction from the faulty wheel. There may also be vibration on the steering wheel or brake pedal. In the later stages, the wheel may be jammed.
Can only the outer ring of the bearing be replaced?
No, the mortar bearing on Skoda Octavia A5 It's a non-collectible node. Replacing only a part of the bearing is impossible and inefficient. The entire assembly must be changed.
Is it necessary to do a wheel alignment after replacement?
Yes, I will. Replacing a hub bearing requires unscrewing the levers and ball supports, which inevitably changes the angles of the wheel installation. Without correction, the tires will wear unevenly.
How long does it take to replace a bearing?
An experienced master spends about 1.5-2 hours on one side. If you donβt have a dedicated tool or experience, the process can take 3-4 hours. Do not rush, because the quality of work is more important than speed.