Naughty Noddy started making a noise a couple of weeks ago, I thought it was probably a grumbling wheel bearing that could wait a while. Sadly the noise got louder much more quickly than I had anticipated so I decided it was time to do the job, even though it meant doing it on the drive rather than on the 4 wheel lift. There are loads of youtube videos to explain the job, it's really not that involved but I do recommend you have 2 jacks - one to lift the car and one to lift the suspension arm off the lower ball joint bolts. Lift the car in the middle by using a long length of wood or steel box, you can then use an axle stand at the jacking point to make sure you are fully safe. My job started off going quite well but the drive shaft really didn't want to come out of the bearing - it took a lot of battering, loads of w40 and ultimately a good twatting with a very large club hammer. The drive shaft is splined, as is the bearing and once rusty there is a very large area to stick and they can be a complete pain to separate. I had used some metal blocks and the wheel bolts to create a makeshift puller, I think that helped a lot, as soon as it had moved a few mil it went fairly easily. It was, however, more than a match for my cheap Chinese puller, which just bent under the strain. I must get some decent old British or American ones some time.
If you do this job on any car be sure to use a cable tie or similar to hold the brake caliper up and out of the way, you don't want it dangling on the hydraulic hose. Also never, ever hit the end of the drive shaft to dislodge it from the bearing, you will damage the threads and a new drive shaft is not cheap. Remember to knock the locking part of the nut in to the recess in the drive shaft so it can't come undone, obviously do it up very tight first - about 150-180NM is where you want to be - that's a fair bit tighter than a wheel nut, it needs a fairly long torque wrench.
The car now rolls silently and is much mire pleasant to drive. Just to finish, the way to tell if a grumbling noise is a wheekl bearing listen to see whether the noise increases when you go round a corner. Mine would g quiet in a right hand bend, get noisy straight on and even noisier in a left hand bend - that's how I knew it was a right hand bearing. I jacked up the right hand side and spun both wheels by hand, the front was clearly where the noise was coming from.