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Replacing the rear wheel bearing

Wheel bearing failure can be catastrophic so it is important to change them when you first start experiencing problems. Typical symptoms include, but are not limited to, the following:

  • Rumbling sensation when braking or driving along.
  • Excessive noise from the wheels when braking.
  • Poor handling when braking.
  • Knocking or rumbling when cornering.

To check your wheel bearings, jack up the rear of the car and grasp the wheel at the top and bottom. Rock the wheel back and forth and look for play in the bearings. Spin the wheel as well. If it sounds rough, then the bearings are probably on their way out.

In this guide, we are going to replace the wheel bearing and hub assembly. The rear hub assembly is available from smart at a cost of around £70.

To replace the assembly, ensure that you are parked on level ground. Chock the front wheels, slacken the wheel bolts, jack up the rear of the car and remove the wheel.

Support the rear of the car on axle stands. Use the subframe and not the De Dion tube as we need this free to move.

Unfortunately the bolts that secure the rear hub assembly are obstructed by the driveshaft. Therefore, the driveshaft needs to come out. To do this, remove the bolts holding the lower arms of the tie bar.

Use an E16 socket on the bolt. Hold the nut on the rear with a 18mm ring spanner (if you have a mk4 or earlier, you won't have to hold the nut as it is welded to the axle). Support the De Dion tube beneath the rear brake drum with the jack to prevent the bolt from binding. There will be a small amount of tension released as the bolt comes out.

Carefully lower the De Dion tube on the jack. Check the axle stands haven't moved. Now repeat for the other side. Both tie arms need to be free.

Use a 13/16 AF imperial socket to remove the long driveshaft bolt as shown. You will need a long bar to do this as it is held tight.

Undo the bolt on the front of the brake drum with a TX30 bit. Release the handbrake before you try and remove the drum!

Pull the driveshaft out of the back of the hub. You may need to pull the De Dion tube towards you to make enough space. Make sure the car is supported well before you do this.

You can now access the four E14 bolts on the back of the hub.

Remove all four bolts, hold the backing plate for the rear brake and carefully pull the hub free from the car.

The hub has a lip on the back which stops it falling off as you remove the bolts.

As the hub becomes free, we used one of the bolts we removed to hold the brake backing plate to the axle. In this way, you avoid putting stress on the brake lines.

You can now replace your old hub with the new one.

the hub doesn't have a particular 'way up'. Just ensure you don't trap any dirt as you bolt the new hub through the axle and rear brake base plate.

Reassembly is the reverse of removal.

Torque settings:

  • E14 hub mounting bolts: 65Nm.
  • TX30 brake disk securing bolt: 6.5Nm.
  • 13/16 AF Driveshaft Bolt: 30Nm + 90°.
  • Wheel bolts: 110Nm.

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