Please do this at your own risk. I am not responsible if you break anything. End legal mumbo jumbo. This DIY was performed on a 1984 318i, M10 engine, manual transmission, alpine white paint, a little rusty, you know the drill. So if that is not your car, there might be a difference. I might not know what those differences are, sorry.
Alright, if you drive an E30 and your wheel shakes, makes grinding noises or wobbles when turning.... this is for you!
Here's a list of part numbers that you will need for this specific project:
New rotor hex bolt: 34111123072
New axle retaining bolt: 31211125826
New wheel bearing (or hub): 31211131297
New bolts for brake caliper: 34111154445
New bolts for brake carrier: 34111118948
New dust cap: 31211130125
You will also need a hub puller, a torque wrench that goes up to 250 ft.lbs and huge socket.
That should do it.
To start: loosen up lug nuts when car is on the ground, block the back wheels, jack up the car and take off the wheel. This is what you should see:
Okay, now the things that are going to have to come off before reassembly are the brake caliper, brake carrier, brake pads, brake rotor and finally the wheel bearing. To get most of these parts off, you'll have to use a lot of force. How do you get a lot of force on a rotating circular object suspended in the air? Lotta friction. So, apply the brakes.
To start the disassembly, somehow pry the dust cap off. The dust cap is not as big as it seems, so you will probably end up denting it or messing it up beyond reuse. (So buy and extra.) Here's the RealOEM exploded diagram: the dust cap is #4, the axle nut #3 and bearing #1.
Here's mine with out the dust cap on:
See that huge nut? Yeah. Here's where my first problem came in. The space in between the nut and the collar of the bearing is very small and I don't keep a supply of thin walled, big sized sockets around, so it took a while to locate one. Once you get the socket (I don't remember the size anymore), you are going to need a lot of torque to get it off (it's tightened down to 210 ft.lbs). So, have a helper get in the car and apply the brakes, firmly. Break the bolt loose, but don't remove it. Also, at this time, break loose the brake rotor retaining hex nut, it's easier at this time.
Next, look behind the rotor and disconnect the ABS (if you have it, I don't, so I don't know where it is) and disconnect the brake wear indicator sensor (if it isn't cut up and taped together like mine was). So, I don't really know where it is on the E30, but on the E36, the brake wear sensor is in the brake pad and the ABS is "under" the pad.
Now that you don't need the brakes anymore, it's time to remove them. Look behind the caliper and locate the 2 bolts holding the caliper onto the caliper carrier. They are 16mm.
Take those off, including the pads, hang the caliper up with either a hanger, zip tie, bungee cord or what have you. You really don't want to rip a brake line.
Now for the caliper carrier. There are two bolts holding that one (19 mm), one on top, one on bottom. They attach the carrier to the spindle. Take them off and remove the carrier.
Next, remove the brake rotor. To do this, you need to remove the rotor retaining hex bolt on the face of the rotor. That's the only thing holding it in.
If you loosened it earlier, this will be easy, if not, spray some WD-40 on it and make a sandwich. Anyway, take the rotor off and take a look at the wheel bearing.
That's pretty. Now, some people like to beat it off with a hammer. My dad tried it and it definitely failed miserably. Get a puller from your local auto parts store.
Anyway, use the instructions or figure out your puller for yourself. There are many different kinds. The operation kind of reminds me of spring compressors, so that might help. Anyway, pull the bearing off.
Now, here's a comparison of the old vs new bearings:
Now, the old one obviously doesn't have the gear looking thing on it while the new one does. Why? ABS. BMW stopped producing non-ABS wheel bearings a while back and it's okay to replace it with the new one, don't worry. Fitment is not a problem.
Anyway, it the dust shield (part #2 in the Real OEM diagram) came off with the bearing, put it on the new bearing. Easy as pie.
Now for the somewhat tricky part: you have to put the bearing on the axle perfectly
straight or you will have to pull it off and do it again. Hopefully if you do it right, you won't know what I'm talking about. Get the bearing all the way on the axle shaft, being careful not to damage the innards of the bearing (i.e. don't snack them with a hammer). Put the new axle retaining nut on the end of the axle, but don't tighten it just yet.
This is what you should have.
Okay, put everything you took off back together. Keep in mind that the bolts for the brakes are only designed for one use. So slap some new ones in and be sure to put LocTite on them. Torque the rotor retaining hex nut to 12 ft.lbs and the bolts on the brake calipers to 81 ft.lbs.
Once you have the brakes reinstalled, use them. That is, to help you with tightening the axle nut to 210 ft.lbs. It also helps to put the lug bolts in the brake to keep the bearing from spinning.
Once you're all done, clean up and take your noise/shake free car out for a ride!