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Handbrake Shoes replacement

DIY: 
36K views 12 replies 11 participants last post by  boris1 
#1 · (Edited)
My handbrake haven't been grabbing ever since I got the car, it bearly hold on even the slightest of hills. So when I was doing recon for a rear wheel bearing job, I decided to replace it. The job is relatively straight forward once you remove the rear caliper and rotors, but putting back the retaining spring proved more difficult than I had bargained for. Since I did not see a handbrake DIY, I decided to make one.

First all the tools you need for the rear brake shoes.


If you haven't done a brake job before, follow prep work steps 1 through 5, you should arrive at the picture below:

1. Loosen rear wheel lug bolts, chock front wheels, jack up rear of car, place on jack stands, remove rear wheels.
2. Use 16mm ratching wrench to remove pair of brake bracket bolts, remove brake bracket with caliper attached, hang with zip ties.
3. 6mm hex key, remove 2 rotor retaining screws per side, if you strip it, grab a 3/16" carbide drill bit and hit it, regular drill bit does not cut it, then use screw extractor.
4. Make sure parking brake is down, remove rear brake rotors, if rotor is seized, hit with a sledge hammer, do same on other side.
5. Release some tension on parking brake cable, open up boot behind brake lever, loosen two sets of screws, 9mm and 12mm deep sockets.


Now you're ready to remove the old shoes, I tried various ways and destroyed an old spring in the process, in hind sight, do this.

6. Use a flat screw driver or any strong picking device to pull the top retaining spring hook and pry it out of the slot.
7. Fit 5mm hex key into side springs, push inward and turn 90 degree left or right to unlock, will pop out automatically.
8. Spread brake shoe outwards, it will fall off the hub, unhook bottom spring and remove adjuster screw.


9. Thoroughly clean mating surfaces with brake cleaners, and all reusable parts, here a shot of new vs. old (rusted, pitted) hardware.


10. Hook up a dremel or other rotating device and a grinding disc, cut and clean the rust inside the brake drum.


11. Apply a thin coat of anti-seize to area on backing plate where shoes slide when they expand.


12. When putting back the new shoes, after much trial and error, I found the following sequence to be most effective.
a) Position adjuster screw between bottom notches of new shoes, screw facing rear of car.
b) Hook on bottom spring, collapse shoes toward each other to facilitate this, then spread outward.


c) Spread shoes around hub from bottom and raise to position, align top notches around brake line expander.
d) Insert fixing screw on each side into middle hole on each brake shoe, pass through backing plate, turn 90 degrees to lock.
d) Here comes the tricky part, hook one end of top spring to one shoe, leaving about 10mm between other hook and its slot.
e) Use hooking end of drum brake tool, pull the spring hook towards the slot, it required quite a lot of force, I was losing grip with my shoes on the ground and I weigh close to 180lbs. As you set the tip of the hook into the slot, carefully rotate spring hook tool to release while maintaining pressure on spring hook with tool in other hand so it doesn't back out. DO NOT use fingers for this, as if and when the spring snaps out, it'll guarantee you a cut and bruise.:crying: I stumbled onto this method after 30 min of agony on one side, and 5 min of breeze on the other.


13. Adjust new shoes, this step is simple yet time consuming, you want to find the right slack so the shoes barely touch the drum.
a) Tighten slack in handbrake cable inside of cabin, pull and release handbrake a few times.
b) Fit rear rotor over new shoes, spin, if too loose, turn adjusting screws to spread the shoes outwards, opposite direction on each side.
b) Repeat until you feel resistance. Fit wheel, pull parking brake up 2, 4, 6 and 8 clicks, test, wheel should lock completely by 8 clicks.
14. Apply anti-seize to hub and outside flange of rotor, fit rotors retaining screws, caliper brakets, wheels, lower car.
15. Go for a test drive, slowly pull handbrake a few times at 15mph to seat the brake surface with the drums. I went for a spin around the Marina.



I felt a noticeable improvement after the new shoes when parking, but did not try to lock up the rear while moving at 15 to 20mph. I hope this helps people to avoid the pitfalls and multiple trips to the hardware store in case something unexpected happens.cherrsagai
 
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#5 ·
What the picture doesn't show is 2 of the old shoes had major pitting, small chunks missing on the surface. The disc had major rust, I must have grounded of more than an ounce of rust off the 2 drums. I'd definitely recommend adjusting the screw and cable first. In my case, I just can't have spare parts sitting around taking up space.hiha
 
#4 ·
Really nice. I'm guessing my shoes are shot - it won't hold on moderate hills at full tightness (I mean using gorilla strength to get the last click on the e-brake). I was planning on trying to adjust the e-brake first, but this'll come in handy when that likely fails.
 
#6 ·
Nice write up.

Given the massive over-maintenance that goes on here, replacing a set of $20 brake shoes seems pretty harmless hiha
 
#7 · (Edited)
Good write up with great pictures. Thanks.

May I add one point.

Due to the M5 having an LSD, it's very difficult to balance the tensions on the cables at the handbrake lever. IIRC you need to set the tension such that each wheel drags quite a bit with the handbrake up by two clicks. When adjusting the second side, due to the LSD, you can't really say which side is causing the drag as both wheels are, to all extent and purposes, acting as one.

I get over this by:
1. Adjusting one side, say the left hand side cable, until the wheel drags on the brake (you know it has to be the left hand brake as the right hand is still slack).

2. I then slacken the adjusting nut (by the handbrake lever) back by a couple of complete turns (so it won't affect/drag whilst adjusting the right hand side).

3. I then adjust the right hand side cable (such that it's drag is as close as possible to how the left hand side dragged) and lock the right hand side nuts.

4. Then I re-tighten/lock the left hand side nut by the two complete turns that were earlier slackened (to get back to the correct setting).


Doing it this way has returned realitively good results, with both sides working pretty much as hard as each other.

The best way to match up the tension is to use a brake testing machine (like they use in an MOT) but most of us don't have access to one of those, unless your MOT centre don't mind you messing with the brakes during the test!

I've not seen a manufacturer that's as difficult to set a good handbrake before. Both mine (m5 and 320) are hopeless and I've adjusted the handbrakes by the book, at one extreme and the other extreme of adjustment, never a great result.

If anyone finds a magic setup, please let us know!
 
#9 ·
A balancing arm in the cabling would go a long way to match up the tensions between both sides, it's a shame they didn't include that type of setup in tge car, many other manufacturers do.

Parking on an incline and seeing how much the car 'drops' both sides (when you take your foot off the brake pedal, leaving only the handbrake to hold the car) is another indicator of how well both sides are matched up, car should drop the same amount both sides.

I wonder if the fact that the discs have an aluminium bell (so the drum section is less rigid) has any effect on the handbrake's performance?
 
#11 ·
I'm going to change mine sometime in the future also I've already adjusted my cables and the brakes still suck.
Every BMW I've had has had a horrible handbrake..
 
#12 ·
Thank you for this DIY! Just did this job myself , and I finally have a working handbrake! The strange part is one brake shoe was gone 100% and the other on was at about 20%... Just wanted to share some photos i took and a video if the brittle brake shoe....


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#13 ·
Actually you can adjust the parking brakes very precisely without any special dynos/tools. Here is how I did it. After refitting new parking brakes, leave one disk/drum off the car. This way you are isolating just one parking brake side with no interference from the LSD. If you take the left disk off, you can adjust the right side as you want. Then take off the right side disk and put the left disk on, and now you can adjust the left parking brake without effects from the right side. Now, if you want to get them really perfect, use a torque wrench with a 36mm 12 point socket on the main axle nut to measure the torque required to defeat the parking brake on one side with the parking lever engaged 2, 3, 4, clicks (probably difficult to measure torque precisely at higher parking brake engagement points). Keep in mind, we are not unscrewing the axle nut, just using it to rotate the axle to measure the torque required to defeat the parking brake. Write down these torque values for one side. Now remove the disk on this side, put the disk on the other side on the car, and now play around with the shoe adjuster at the wheel and the cable adjuster in the car to get the same torque values at 2, 3, 4 clicks on this side. The good part is that the overall torque drag of the axle bearings, axles and differential are the same whether you are measuring the breakway torque for the left or the right side (while the other disk is off the car), so this driveline torque does not alter the results. Hopefully this makes sense, if it doesn't I am happy to clarify.
 
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