Right well my weekend was certainly a busy one, but luckily I managed to avoid going bridesmaid shoes and tiara shopping by servicing beccas uncles vans. They are 1.7DTI combo vans which are based on a corsa, however the brakes are pretty similiar to an Astras brakes. Now I've never changed discs before (although done pads hundreds of times). But as I was amazed just how easy it all was I thought I'd post it up here.
This is only rough so its no difinitive guide but I thought the insite may give others the confidence to get out the spanner and give it a go.
OK first things first.
Hand brake on and chock the rear wheels to prevent them from moving incase the hand brake cable snaps. Keep keys in the ignition to allow you to turn the wheel once off the ground.
Undo the nuts on the wheels, just enough for them to become loose.
Open the bonnet.
Jack up the car using its jacking points and support using axle stands.
You should have something looking like this.
Locate the brake fluid resevoir and take the cap off.
OK what your looking at here is the brake caliper (thing that says lucas on it). The caliper holds together the brakes with the brake disc located in the middle. The discs pins and when you brake the brake piston pushes the pads together which bite onto the disc slowing the car.
First thing to do is to take the pads out to allow you easy access. So to the far left of the lucas sign embossed is a bolt undo it.
Once the bolt is removed you can now move the caliper upwards.
I've used a cable tie to keep the caliper up whilst I'm working. With the thick end of the cable tie going through where the bolt we've just removed was.
This is what you see now. The rusty disc with the pads either side of it. Flick the pads outwards away from the disc and they will simply fall out the caliper. At this point if your just changing your pads simply put some new ones in with a little copper grease and your away.
Now then with the pads removed we now want to turn our attention to the discs as these have to come out. To get at the discs you need to remove the entire braking assembly. Before you start going weak at the knees its only held on with 2 nuts.
Can you spot them? They are very close to the drive shaft CV joint in this picture.
Just incase you couldn't see them they are the bloody big nuts above
Now then before you go hell for leather at these nuts you must take in the following. Don't fully remove one nut then the other or you'll end up hitting yourself with the caliper. Untighten them together removing the bottom one before the top one.
ALSO the brake pipe which contains the brake fluid is attached and we don't want to disturb it too much. So watch the brake pipe like a hawk. I then put the entire assembly on the lower wish bone like so...
Below is the entire assembly in my rubber glove mmmm rubber so soft and errrr
Next up is the manky old lipped and scored disc. One screw and off she came.
Screw on the right of the hub.
The hub minus the disc.
Next up get your new discs and wipe over both sides with some petrol. This should remove the grease or lubricant that they put onto the discs for transit.
The fitting is reverse of removal. So disc in place and screw back in.
Caliper bolts back in place.
Next get your new pads and apply a little copper grease to the edges that slide into the caliper
Put your new pads in.
Once done you'll find you cannot close the caliper down over the new pads. This is because the brake piston will be sticking out (as your old brakes had worn down the further it will stick out). So we have to push the piston back in. The piston looks like so...
Obtain a G clamp and begin tightening and watch the piston move backwards.
Remember we removed the brake fluid resevoir cap?
This is to allow the brake fluid to reenter the reseveroir without causing any issues. I recommend that you do one side at a time to avoid any spillage. If it looks like its going to spill, use a turkey baster to suck it out and put it back in once done.
Once you've done this apply copper grease to the piston itself on the part that will make contact with the rear of the brake pad.
Refit the bolt now you can put the caliper over the new brake pads
Doesn't that look better?
Now replace the brake fluid resevoir cap and hop in the car and pump the brakes till it goes firm again.
Remove the axle stands and lower the car and tighten the nuts on the wheels again and replace caps.
Start up the car and once again pump the brakes. Remember to bed the discs and pads in as per the instructions and remember when your first testing the brakes just start off at slow speed and once happy begin to increase the speed.
Hope this helps someone if only 1 person to get out there and save themselves some dosh. I'm sorry its not an astra but my calipers are nearly 100% the same. Its only a rough guide and I strongly recommend using haynes to backup everything you do. I take no responsibility at all for anything ever.