Guide to fitting Defender Rear Wheel BearingsJan 22nd, 2011 | By Pod51 |Category: Defender How To Guides
Symptoms of Bad Wheel Bearings
Learn to spot the signs of bad wheel bearings.
Wheel bearings are critical to the proper function of a vehicle’s hub, tyre and wheel assemblies. By allowing friction-free movement and rotation of a vehicle’s hub assemblies, wheel bearings promote smooth vehicle tyre and wheel motion. Bad wheel bearings, however, negatively affect vehicle tyre and wheel operation and produce a variety of symptoms.
The most common symptom of bad wheel bearings is noise coming from the wheel or tyre area of a moving vehicle. This is often a grinding, grating noise that gets progressively louder as the vehicle is driven faster. Bad wheel bearings are easily heard, but often not easily diagnosed, at least initially, because they are not a common vehicle part that needs to be regularly serviced or replaced. This means many people are unfamiliar with wheel bearings and the noises they can make when they go bad.
Although excessive wheel noise is the most common symptom of bad wheel bearings, many times a vehicle with bad wheel bearings will not have any noise coming from the wheel or tyre area at all. Wheel looseness, or wheel play, is a common symptom of bad wheel bearings. As the wheel bearings degrade and lose their structural integrity inside the wheel hub, they can allow the wheel hub and spindle to become loose, which ultimately gets transmitted to the vehicle wheel and tyre, a condition that can be diagnosed by raising the vehicle, grasping the suspected wheel and pulling on it.
Wheel Rotation Restriction
As wheel bearings corrode and/or become pitted and lose their smooth exterior linings, they inhibit the smooth, unobstructed rotation of the wheel hub and spindle assembly, which in turn restricts the spinning motion of the vehicle wheel and tyre. This restricted wheel and tyre rotation presents itself many times as the vehicle pulling to one side during normal operation, or as the vehicle requiring increased acceleration to attain normal vehicle driving speeds.
Abnormal tyre Wear
If wheel bearings become bad enough, they can have a negative impact on the wear patterns of vehicle tyres. Wheel bearings contribute to the overall structural integrity of a vehicle’s wheel assemblies, which house and anchor a vehicle’s tyres. Wheel bearings that become extremely loose or degraded can cause excessive wheel and tyre play to develop, and this excessive play can place abnormal stress on a vehicle tyre. This stress causes abnormal or premature tyre wear to develop.
Front Suspension Looseness
A vehicle that has bad front wheel bearings will often exhibit symptoms of having loose front suspension parts, including symptoms of tie-rod end looseness or control arm bushing looseness. When tie-rod ends and control arm bushings wear excessively, they can produce similar symptoms to that of bad wheel bearings: tyre/wheel looseness and/or vehicle front-end sway. Many times bad wheel bearings, especially bad bearings that produce no noise, are diagnosed after eliminating any vehicle front suspension abnormalities as the cause of any suspicious wheel/tyre looseness or front-end sway.
How to fit Wheel Bearings
First things first, you’ll need to remove the wheel.
Now you will need to slacken off the wheels nuts as were going to be removing the wheel. Seeing as your there and to save time it would be wise to slacken off the flange nuts.
Now jack up the axle and remove the wheel, you might as well put an axle stand in too as it makes things easy (You’ll need one anyway when it comes to putting the wheel back on).
Now remove the circlip from the half shaft, remove the drive flange and then pull out the half shaft.
Now bend back the locking washer. then using a box spanner/hub nut spanner undo the lock nut (You can use a chisel to knock the nut round but its not recommended unless absolutely neccesary). Now remove the washer and undo the remaining nut
Now whilst holding the seal with your thumbs give the hub a tug and remove it.
Next remove the inner oil seal (because its the easiest) and remove the inner race
Now its a case of flipping the hub over and using a drift/ punch/ old screwdriver/ to knock the outer out. In some cases you may have trouble getting the outer seal out so you may need to knock the whole bearing and seal out from the other side.
Here’s a handy tip for knocking in the new bearings and seals. Cut a piece out of one of the old bearing outers. Use this to knock the seals and bearings in.
Due to the cut it won’t get stuck in the hub .
Next its onto putting in the inner bearing (note the old ring) knock it into place (if it’s not in far enough, then use the other old ring to drive it home).
Now take your time doing the next bit. Pack the new bearings with grease until you can not get any more into them and drop it into place and fit the new oil seal using the old ring again.
How to pack bearings with grease
Place a large dollop of grease in one hand, while you use your other hand to move the bearing.
Take the bottom of the bearing (the wider side), and, holding it vertically against the grease in your hand, scoop the tight area between the cage of the bearing and the hub of the bearing. The key is to fill the cage of the bearing that holds all the small bearings in place. To fill the cage correctly, you need to pack a small amount into the limited space. It will take time and repetitive motion to fill the bearing properly.
Turn the bearing every so often as one area of the cage begins to fill with grease and keep packing more grease into the cage. You will have to get more grease as necessary, and you will have to work the grease being slid up the palm of your hand back downward.
Move all the way around the bearing, and when you can see grease coming from the entire circumference of the area between the cage and the hub of the bearing at the top tapered side of the bearing, you’ve packed the bearing. Wipe a layer around the side of the bearing before installing, and use the rags to wipe your hands.
Now where were we ..
Now flip the hub over and do the same again.
Refitting the hub is pretty much the reverse of taking it off so retrace your steps.
One exception to rebuilding the hub etc is when you come to fit the first big nut, tighten it right up and then slacken off nearly a 1/4 turn back. Either fit a new locking washer or if the old one’s only been used once, flatten it out and re-use. Check manual or Rave CD for torque settings and that’s about it.
Oh and it might be a good idea to get a new drive flange and gasket.
[review pros="Peace of Mind Knowing they are done, Smooth running, better steering etc" cons="None really just a bit dirty and time consuming" score=68]