I’m going to assume you are replacing the old brakes with new ones, so there’s a couple of tips for that process included here but if you just want your brakes off completely and have brake line plugs or are cool with brake fluid peeing out everywhere, you can skip past those bits and just check out how to get your brakes uninstalled.
Get your front wheels off and preferably support the car on axle stands (cars are heavy, you don’t want one on top of you).
Removing your Audi A4 stock brakes – tools
To remove the stock brakes you’ll need these tools:
- 21mm socket (1/2 inch drive)
- ratchet (1/2 inch drive)
- breaker bar (1/2 inch drive)
- 11mm open-end spanner
- Penetrating spray/WD40
- wire (old wire coat hanger)
- paper towels/rags (to catch and clean up brake fluid spills)
Not essential but highly recommended:
- 1/2 inch drive, sliding tee
- your a4’s emergency 17mm wheel wrench (to use as a bar extender)
- lump hammer
- 11mm brake line spanner
- gloves (because brake fluid is hugely corrosive)
In an absolute emergency:
- Vice grips!
Space is tight behind your wheel hub where the caliper mounts and without a professional workshop lift it’s not as easy as just throwing the right socket onto a breaker bar and busting those nuts (so to speak). On a standard jack you can create some extra room to work by turning the steering around to full lock. This will allow you to get a breaker bar on one of the two bolts but the other will require some creativity.
I found the only tool that would fit into the space was a sliding tee bar with the emergency wheel wrench slid over it to create an angled extension. Sometimes this alone has worked but other times I’ve also had to bash on the extension with a lump hammer to free the bolt. Maybe you’ll have something more appropriate in your toolbox but I’ve helped swap the brakes on these A4s a bunch of times now and that janky wrench extension trick has worked every time. It’s just the perfect length to fit inside the arch.
I’ve specified half inch drive sockets as anything smaller and you’re almost certainly going to snap your tools. These cars are old, the bolts are old and unless you’re really lucky they’re seized on TIGHT!
Okay, let’s get stuck in!
Removing your Audi A4 stock brakes – guide
If you need your car for work on Monday don’t start this on a Sunday afternoon and expect to get it done by dinner. You WILL find a seized bolt or nut and it WILL take much longer than you would otherwise expect. Start on Friday night and set aside the weekend. If you’re lucky, the car Gods will admire your preparedness and bless you with no corrosion on your bolt threads (though I have never been so fortunate).
You will very likely need to spray up all your bolts with penetrating fluid (numerous times!) and leave it to soak in and do its job. Because of this chuck some cardboard down under your wheel hubs to catch all the nasty overspray and brake dust you’ll wash out, it’ll help prevent staining your driveway.
As mentioned earlier turn your steering to full lock and see if you can get a breaker bar on one of the bolts. Once you crack a bolt loose, throw the 21mm socket on the ratchet to finish it off. I only ever managed to get the breaker bar to reach the lower bolt (I think), which ever it was there was no room to get the breaker bar on the other and so the sliding tee bar came out.
Wrangle the tee bar into position around the suspension arms and find a way to slide the emergency wheel wrench onto it, experiment to find wherever gives you the most leverage. If brute force and swearing doesn’t budge it, hold everything in place with one hand and give the wrench extension some hefty whacks with the hammer. This has never failed to get these bolts moving even if I sometimes needed to revert to unlock spray or WD40 and come back to it later. That’s my method, it’s never let me down.
Once you get one caliper unbolted, get your wire ready to hang it from an upper suspension arm (you don’t want to leave it hanging from the brake line or wear sensor cable) then persuade it back off the disc. The hammer can sometimes come in handy for this too if your discs are old and have a bit of a lip on them.
When the caliper is free, tie it up out of the way with the wire and disconnect the wear sensor. Leave the brake line connected! If you lose the seized bolt battle with the other caliper you want to be able to put everything back together so you can drive to a garage and let them at it with their air tools. Plan for the worst!
Once you’ve tackled both sides, leave your old brakes hanging, they’re fine where they are. You’ll want to make sure your new brakes fit especially if you’re using non-standard parts. Until your new brakes are bolted in place there’s still room for you to screw this up and so we’re giving you a chance to put things back together if you hit a problem your toolkit or ingenuity can’t solve.
Assuming you’ve got your new brakes to bolt on and everything fits correctly, now we’ll disconnect those brake lines so you can connect up the new ones.
We’re going to leave the original brake lines connected to the caliper and disconnect them from the car. The flexible brake lines connect to the hard-lines with a spring clip and 11mm flare nut. If you don’t have any corrosion you might be able to get these undone with a standard 11mm open-end spanner. If they’re a bit rusty and seized a brake line spanner will grip better and reduce the chance of rounding the nut. Obviously spray on some penetrating fluid to help you beat the rust too.
If you’ve tried a brake line spanner and the nut is still rounding, I have had success with vice grips. They’re a last-resort as they will damage the nut, but if you’re at this stage you’re probably desperate and the nuts are already wrecked and need replacing anyway (a ball-ache job for another day – probably not a DIY).
Should luck and/or penetrating fluid prevail and you disconnect the old brake line, brake fluid is going to start dripping out. If you’re fitting new brakes immediately connect up the new line. If you’re not fitting new brakes I’d recommend plugging the line but you could just let all your fluid leak out if you’re a psychopath.
Do the same on the other side and you’re done; your original front brakes have been removed.
[ Photos to follow ]