How to Bleed & Flush Brakes

Bleeding your car’s brakes is essential if you’ve replaced your calipers or brake lines, and flushing your brake fluid is a great way to improve pedal feel and is a necessary service item every couple years. So, how do you do it? Here’s how, on my Audi S4!

First up, you’ll need to jack up the car and take the wheel you want to start with off. Conventional wisdom says start with the furthest caliper from the ABS pump. You’ll also want to pop your bonnet and find your brake fluid reservoir. Crack the cap loose and top it off with fluid. If you are doing a flush, use a turkey baster to suck out as much fluid as you can before replacing it with fresh fluid.

Once that’s sorted, you can get to bleeding. Find the bleed nipple on the caliper, pop off the dust cover and use the correct size spanner to crack it loose, then feed your brake bleeder tubing over it. Have someone pump up the pedal, then hold it down so you can open the nipple and let the old fluid and air out. Tighten before the pedal is lifted again. Repeat that a couple times per wheel until the fluid that comes out looks clean and air free.

Then repeat on the rest of the calipers, remember to top up the fluid as you go! Make sure you don’t get any DOT fluid on your paint as it is really, really bad for it, and plenty toxic so gloves and rags or paper towels may be useful too.

And that’s it, all sorted. It’s a fairly simple job, just takes some time, but can make a big difference to the brakes feel and performance, and as preventative maintenance.