E39 Brakes

[jhjacobs]

I need a brief rant. I was supposed to spend most of the day working on the calendar but I had to install brakes on my 540i.

Picked up slotted, drilled rotors, cool carbon pads, new sensor wires, and new hold down screws from BavAuto. A straight forward job, maybe 3 hours for all 4 wheels.

I get into the front first. The calipers are held on with 18mm bolts. I don't own a socket, flat wrench of anything this size. I have worked on German cars for a long time and used 17mm, 19mm but never 18mm. I gotto buy a new tool and lose an hour of work time!

After pulling the first caliper its time to pull the rotor. Not possible. I have to resort to the biggest, baddest, most viscous puller I own and it finally comes off. Aside from bending the tiny pins in the sensor plug things go swimmingly until the rear brakes. The calipers are held on with 16mm. I did own this size socket but I have never used it before. When did BMW go in for equal opportunity bolt sizes? It used to be that 7, 10, 13, 14, 17, and 19mm were plenty!? Anyway, both rear disk were on so tight that my puller actually broke off huge chunks of disk material and had to be reset several times on each rear wheel! I was even using WD40. Is this normal for newer BMWs?

After finishing up I even read the brake bedding instructions and followed them closely. Maybe they will be okay for a while now.

Does anyone know about "Cool Carbon" pads from BavAuto? They are almost double the price of normal pads I bought them (yes I am a sucker). I curious to know how badly I wasted my money.

All done now and working away on the calendar.

 

[Bill Riblett]

My sympathies extended!
One suggestion though, WD40 is not really a penetrating oil. Get something like PB Blaster, Kroil, or BG InForce. I especially like the latter 2, but PB Blaster is easier to find. I use Kroil on any fastener on the older cars that hasn't been loosened recently. This has really cut down on broken bolts.

Another thought, a little late, is to use anti-seize on the mounting surfaces of your new rotors, since we know it won't be long on a 540 before you have to replace them again!

 

[jhjacobs]

Thanks for the sympathy and suggestions. I don't think that penetrating oil would have helps much - I was looking for my Macs Marvelous Mystery Oil but I couldn't find it; it showed up later in the evening; figures. In the old days I would often use a propane torch to help convince stubborn disks and drums loose. However, with all the ABS goodies and such I am reluctant to apply serious heat. After I installed all 4 rotors I thought it would have been a good idea to lub the mounting surfaces - I generally keep aluminum grease for this purpose. Oh well.