BMW E90 DIY Front Brake Lining / Pad Change

2007 BMW E90 N46B20

Mileage: 67k km

Early January, OBC said my front brake linings can last another 2.5k km.. 2 weeks later or 1k km later, I’m at –500km !! Hence, the following DIY..

Been changing brake pad since I first own cars.. and still doing it to my other higher mileage Toyota mini MPV.. refer to my archive.

Here goes:

1) Use a brick to block the rear wheel to secure the car preventing it from slipping of the jack.

2) Turn the steering to the right for a left wheel job so the brake caliper is exposed.

3) Loosen the wheel lugs before jacking the car.

4) Jack the car.

5) Unscrew the lugs and remove the wheel. The wheel tend to seize at the rusty wheel hub and require some effort to knock the wheel out. I used a rubber mallet. So worry the jack slips while I hammered it. Check out the rusty wheel hub.

6) Unplug the plastic protective plugs, item 7 below so we can reach and unscrew both the upper and lower guiding bolts using size 7mm Allen key wrench, item 6.

 

7) Use a sharp plier to slide the guiding bolt out so we can lift up the caliper housing.

 

8) Carefully remove the brake wear sensor. It can be recycle depending on the condition of the sensor. I’m not so lucky because I broke mine. I pulled/forced it out before opening the caliper housing, hence snapped into 2 pieces..

9) Slot in a metal bar or wrench handle into “X” below and use it as a pivot to push the caliper piston back into it’s camber, to make room for the new lining. Make sure you apply force to the center of the piston surface so even pressure is applied. Uneven pressure make damage the piston seal in the long run.

Make sure you monitor the brake fluid reservoir so it does spill/overflow. Remove any excess brake fluid carefully because the corrosive fluid can damage our car’s paint. If contacted with the car’s body, immediately rinse off with water, wash with soap and wax it.

Also please note that the 2 guiding bolts need not be taken out entirely.

10) Clean the slots where the lining seated, it’s filled with brake dust. The clean seat allow the lining to slide in and out during operation, prevent sticky pads. The lining over the caliper piston is plug into the piston cavity, so need to apply some force to unplug it.

11) I prefer to install the brake sensor before returning the caliper housing into place because I can see how the sensor is seated without the brake disc rotor blocking my view. You may do it later.

More photos:

Pad/lining that I use. TRW brand.

Close-up on the sensor

Old vs new

The bill, yup! I bought both front and back, same price. For E90, only the front left and rear right has sensor.

Notice how I use the wheel to support the rotor, just in case the jack slipped.. Also notice the L-shape bar on the lower right corner? I used that to push the caliper piston returning it back into the piston camber.

By the way, have fun figuring out how to reset the OBC counter.. haha!

Thank you for reading!

DIY Avanza Front Brake Pad Replacement (2nd Set)

Mileage 113k km, last front brake pad change was 50k km.

New replacement part chosen this time. RM90/-


Tools needed, and of course, the OEM jack.


After remove tyre, check out the balance of my front brake pad, no more than 3mm.


Size 14, anti-clockwise, use the small hammer to whack the wrench a bit. Shouldn't be too difficult. Make sure the wrench is securely mounted to the bolt and not risking damaging the bolt.


Pull out the size 14 bolt and lift the brake caliper up.


Un-slot the brake pad, see how thin is the worn pad compare to the new ones.


Relocate the attached shim and the "don't-know-what" to the new pads.


This pad wear indicator is too short to be workable. By the time the brake disc rotor scrub the indicator to produce screeching noise, the pad would be have been all gone and we are running on metal-to-metal!!


Check the brake fluid level before pushing the brake caliper piston back into its chamber. When we start pushing, brake fluid will be forced back into the brake fluid reservoir. If too full, it will overflow and mess up the engine bay. Bear in mind that this brake fluid is corrosive in nature!! Must be careful. If fluid level too full, need to siphon some out from the reservoir before we continue.


This method of pushing the caliper piston back to its chamber is my latest new discovery, after few other fail attempts. Check out my previous post on brake pad changing back in 2007 and see what a fool I have been. My previous method is very risky to damage the caliper chamber because a slight tilt of the pushing angle will permanently damage the cylinder. The damage can result in the piston coming out in an off tangent angle and cause uneven pad wear.


While forcing the piston in, try to get rid of some brake dust stuck in the rubber sleeve. Something I didn't do in the last change. And of course, monitor the brake fluid reservoir level as well. It's raising..


Piston fully recessed into its cylinder. Make sure the loose rubber sleeve is not at the wrong place when lowering the caliper back to its operating position. The rubber sleeve can get trapped in between the piston and brake pad which will potentially puncture the sleeve.


New brake fluid level after one side of the wheel is done.


Now lowering the caliper back to its operating position, with the new pads.


Now move on to the other wheel and after the 2nd wheel, this is the new brake fluid level.


After pumping the brake pedal and driven the Avanza around, this is the latest brake level.


When the wheels are taken out, its the best time to inspect all your ball joints and bushes, they all look good except this!!


This is the front anti roll bar link. See the damage rubber sleeve. The trapped factory filled grease has seen day light and is all over the place.

DIY Avanza Front Brake Pad Replacement

Just bought this set of front brake pad..



Cost me RM95..

The spare shop ask if I wanted cheap or orginal one.. I asked him what's the different, he said the price lor... :-/

I ask him to show me because from the workmanship, its pretty easy to differentiate..

The shop keeper went to the back of the shop and return with only the original and say.. "Aiyoo, only original left woh.."

With no option at all, I just grab loh.. :-/

Mileage.. 50k km..

Step 1: Place a brick at the opposite rear wheel. If you r jacking the front right, then place the brick at the left rear. This is to stop the car from reversing and move on three wheels..


Step 2: Loosen the wheel nuts before jacking the car. This is because after the car is jacked up, its difficult to loose the nuts as the wheel keeps rotating and its difficult to apply force to loose the nuts.

Step 3: Start jacking the car. Please pay attention on where to jack. This is important because you don’t want to jack the wrong place. Jacking the wrong place is both hazard to life and may damage the chassis.


Step 4: Rotate the wheel so the air valve is on top. This is a marker to make sure when putting back the wheel, its returned to its original location. A wrong position may result in vibration. Of course, provided that you don’t rotate the brake disc la. (Trick: If you have to rotate the disc, then screw back a nut to identify the valve location.)

Step 5: Now u can take out the wheel.

Step 6: Get a size 14 ring spanner to remove the bolt as shown on the photo. Normal thread, don’t turn wrong direction. I find many members have difficulty removing nuts or bolt facing inside out. I too, sometimes confuse.. ;D


Step 7: Once the bolt removed, flip the calliper upwards. After which the brake pads are exposed. Just tarik the pads keluar. You may want to use a screw driver to korek it a bit but make sure you don’t apply force that can damage or scratch the disc surface or worst, bend the almost an inch thick disc... ;D








Step 8: You will now notice the used pad have a metal piece sticking out. That’s the wear indicator. Meaning when the pad habis, that metal will scratch against the disc and produce “geeeeek....geeekk...” sound. After which it will leave some scratches on the disc.... :P That’s why I usually never wait until I hear the sound.. ;D Just like the low fuel warning lights. Only good for people who keep forgetting to pump fuel or worst still, seldom pay attention to the guage. That’s why the car designer decided to lit up a warning light when low fuel.. ;D Too bad our brake pad have no “low pad” warning lights. My X-car got, and every time the light lited, I have to fork out RM16 to replace the thingy. It’s a glass-made grounding switch. The moment the pad is too thin, the disc will scratch the glass and break it. Inside the glass got tiny wire which when touch the disc (earth or -ve), the warning indicator will lit.. Ok.. back to Avanza.. :P ;D keltan and rfalmrf.. inspired ??? ;D

The following photo is after I have transfered the metal wear indicator to the new pad


Step 9: On the outer pad, there’s no wear indicator but there’s this metal sheet. Transfer the sheet to the new pad as well. That’s a very important “gadget” to disseminate heat from the pad and to stop or rather reduce vibration on the pad. I just don’t understand why the inner pad tak ada this metal sheet ???


Step 10: Pasang balik the pads.. Viola!




Step 11: The next step is the major reason why many rather let the workshop earn their money. The piston that pumps onto the pad to result force against the disc when braking, needs to be forced back into its chamber. Otherwise, you can’t flip the calliper back to its working position because the now thicker pad will sangkut the calliper.

The right way to do it is using a special tool. I call it a “reverse-clamp” (don’t know its real name.. :P). Like a desktop clamp, but it works on a reverse way. Instead of clamping in, it extend itself outwards to push the piston back into its chamber, with one end on the surface of the piston and one end on the calliper opposite the piston. Using the clamp is easy and can prevent the piston returning in a senget position and damage the chamber cylinder.

This is how I do it… ;D

B4.. look at the position of the piston..


After.. look at the piston position again, it has now retracted into its chamber.. No need special tool.. ::) ;D but make sure you are gentle with it. Don’t force it too hard. A slight senget of the piston will potentially damage the chamber cylinder.. Be careful!


Step 12: After pushing back the brake piston, must quickly check the brake fluid level because the fluid that filled the calliper chamber has now been forced / pushed back to it reservoir and potentially cause overflow to the reservoir if the level is too full. Normally we do not top up our brake fluid because when the level is low, its most probably the brake pad sudah makan and more fluid needs to fill in the calliper piston chamber. This causes lowreing of the fluid level at the reservoir.


Step 13: Return the calliper to its working position and put back the size 14 screw. Then done lor. So simple that I forgot to take photo.. :P realise only after I put back the wheel. Anyway, this is it.. pay attention to the lower size 14 screw. Its now a bit kilat.. :P because we have worked with it.. ;D


Step 14: Now repeat the same with the other wheel.. but I was lucky enough to get an apprentice.. :P ;D who is still on pyjamas.. :P









More photos:
The used pads still have 1.5mm to 2mm but I decided to retire them.. The used ones has DAIHATSU imprints but all this while I not too happy with this original pads. Hope the Toyota brand is better.. :-\


Compare the inner wear among the pads.. not even..


Compare the outer wear among the pads.. not even.. meaning when check for pad wear. Don’t just check one side, must check all sides, in-out-up-down.. Nothing wrong with the brakes. Such uneven wear is common. If you get even wear, now that’s uncommon.. ;D


Fluid level after pasang both front pads. Very penuh because when I did my 40k km service, the SC has replaced the fluid with new ones and return it to MAX level.. without consideration of wear brake pad. See now what happens !!...


I recently bought front brake pads for my Perdana too. Cost me RM75 only.. and check out its wear indicator.. comes with the pads.. Love the blue color.. ;D but too bad different size with Avanza. Otherwise, I would have put it into Avanza.. ;D


WARNING:
1. All brake pads need to run-in and don’t forget to pump the brake pedal a little to force the brake calliper piston to return to its working position when use it for the first time.
2. Check the calliper screw which we buka just now, from time to time to make sure its not loose, I always worry too tight will damage the thread and too loose its dangerous. So got to check frequently. This is a life saving part of the car. Don’t play play. Even the workshop people do also I don’t trust.. :P