Dreading first Brake Job...

[e34.535i.sport]

Hi there. I'm about to attempt to change the rear pads and discs on my '90 535i sport, with standard dealer parts.

I'm not looking forward to the job (have to do it MOT is coming up!) as i've read the haynes manual so many times and searched this forum for so long, and i still don't feel confident in knowing entirely what to do. I also read Bruno's piece which helped a little, but i'm worried about the brake fluid. Is it best just to remove some from the resevoir and re-fill it afterwards? If so how much?

I know its a big ask but if anyone could outline the procedure for me from their experience i would be MOST grateful. I've done a lot of other repairs on the car and maintenance work and my confidence is definitely growing, but the brakes are a big thing for me - if i do it wrong someone could get hurt (not just my wallet!).

I appreciate all advice, thanks, John.

[Ferret]

Hi there. I'm about to attempt to change the rear pads and discs on my '90 535i sport, with standard dealer parts.

I'm not looking forward to the job (have to do it MOT is coming up!) as i've read the haynes manual so many times and searched this forum for so long, and i still don't feel confident in knowing entirely what to do.

Dont worry about the job, it's literally a case of 5 bolts a wheel

You'll need a breaker bar, you wont be able to do this job without it.

Some thoughts:
There's two difficult spots to this - firstly getting the caliper carrier bolts out and then getting the locking/retention pin out of the rotor/disk. If your car is on its original rotors, you're probably looking at a set of seized locking pins - you're going to need to drill them out.

Which means you end up with a hub with half a locking pin in:


You can either drill this and pull the stud out, or if you're lazy like me you'll have only drilled the eact amount necessary to get the rotor loose - and not bother removing the rest of it, using the calipers to hold the new discs in place rather than the locking bolt.

I did get pissed off with one side as my drill was getting flat batteries- and took a lump hammer to the rotor on the opposite side to the locking bolt. The whole rotor just jumped off the hub with about three hefty blows. I wouldnt recommend this though as you then have to somehow extract the bolt from the hub with some sheared metal around it. Chisel and file needed.

Getting the carrier bolts out requires a fair bit of force, but so long as you've got a long breaker bar, they /will/ come out. Having said that - my flat mate who's not particularly a big guy couldnt get them to come out - whereas I could put a bit of weight behind the bar and cause the bolts to pop free. These are easy to do on the front wheels, but you might have to get physical to access the rear ones. For this task you need a high quality socket because of the huge amount of force you need to transmit.

Other things you'll need: Copper grease - if you dont grease up the back of the pads they'll make a horrific noise every time you touch the brake pedal - hugely embarassing.

A good quality Hex drive - avoid the halfords hex drive 7mm tool - mine kept exploding and nearly took my eye out once - they just cant cope with the torque required to get the caliper guide pins out...

I'd recommend a good pair of axel stands for this one due to the force required - although I was and did it on the widowmaker jack that comes with the car.

[Ferret]

I've just remembered that there's the spring on the front of the caliper...

There's a knack to removing this spring - you need two large screwdrivers. You have to lever the spring outwards from the centre back towards the caliper body, then use the second screwdriver to get under the clip points and lever it outwards.

This is quite hard to explain - I might have to draw a diagram but you'll be able to work it out.

[e34.535i.sport]

I'm hoping this isn't the case for me - but pretty much all the jobs i've encountered so far have involved troublesome hardware. My friend bought a HUGE breaker bar last week to get the bolt out of the engine that holds the idler wheel on so at least i can use that...

Unfortunately though I only have hand tools and ironically i went to hafords today and bought a 7mm allen key with a grip on it. I have a little trick up my sleeve for the bolts though as my wheel nut wrench has a hollow inner and works well for extra leverage. To be honest i don't even have a drill - and if i did i wouldn't know how to drill a bolt out!

My car has 150k miles on the clock, so i'm presuming the discs've been changed... however the fuel filter hadn't been changed since 1993 (14yrs) when i done it a week or so back - which is pitiful of the PO.

I do a lot of work on the jack - normally put an axle stand under just incase but i am amazed at how well it works! My friend just purchased a '92 e36 320i, now the jack that comes with that is SCARY! Recently i changed the sway-bar links by hand without a problem on the jack, took some force but no hernias etc.

Did you siphon out any brake fluid when doing your pads/discs? A big syringe would be very handy...

I just need some good luck with these bolts first of all...

Thanks a lot for the swift input.

[leicesterboy15]

I have these fun and games lined up soon, good luck and let us know how you get on! Have you priced up standard dealer parts with upgraded aftermarket ones? I wouldn't be surprised if they were about the same price. On my 535 a set of adjustable shocks (Spax i believe) were half the price of the replacement mtech ones from BMW and I had it on good advice that they were as good if not better and I got a good stainless Exhaust much cheaper than the BMW supplied one which would eventually need replacing anyway. Just a thought..

[e34.535i.sport]

Hey there yeah i done just that today; went to research some non standard performance parts (pads and discs) in a BM place nearby and he quoted £100 inc VAT. I ended up getting stock parts for £107.98 which i would always prefer to use (i don't know why!).

I hear you on the exhaust though, definitely the way to go. Luckily the Po had the exhaust done not long before i bought the car - all looks amazing underneath.

The M-tech shocks are £500 each from the dealer! I was literally scared when I asked, but the parts guys in the local dealer are very down to earth so we had a bit of a laugh over it. I will definitley be going with aftermarket versions when they need doing, which i'm hoping isn't soon.

I'll let you know how i got on with the brakes though, and i'll get a write up done to help any other rookies like my fine self!

[Zeuk in Oz]

Just start and see how you go. You have nothing to fear but fear itself. If you run into a snag, just post a question. As for doing it properly, have no fear - it is mechanics by numbers - you can't do it other than the right way.

I have just replaced rotors, pads and sensors on both of my E34 vehicles without any significant dramas at all - didn't need to drill anything out - just needed a little leverage ! I have now just started on my E39.

I just have a mottley collection of tools that seem to do the job.

Trust me, if I can do this, anyone can.

[Ross]

It's peanuts.
Read the Bentley, clean the crap out of the disc retaining bolt and give the proper size hex socket(6mm?) a good whack into it before attempting to unscrew it.

[Jeff N.]

Are you replacing your fluid or just concerned about overflowing the reservoir with new pads?

If replacing the fluid - yes, it helps if you can suck out the old fluid from the reservoir first. Not required but maked the job a lot faster.

If just concerned about overflow due to the new pads, it really depends how close the fluid is now to the top of the reservoir. If you have about a 1/2 inch of space or more, you should be OK. Do the first brake and then see how much it moves up.

You can replace the pads and rotors without cracking the caliper lines. If you crack open the caliper lines, you'll need to bleed the brakes. Avoid cracking them if you can.

Oh yes - latex work gloves or similar are a godsend when doing this job. Brake dust and brake fluid co-mingled are amongst the worst and grimiest things ever.

[Bin_jammin]

Widowmaker jack? My buddy emailed this to me months ago, I couldn't breath I was laughing so hard