The Brake Job

This post is titled: "Changing Audi S4 Rear Brake Pads" or "How to Induce Enough Stress to Loose Interest in a New DIY Hobby"


This is a step by step brake pad replacement tutorial based on my personal experience over the past two weeks.

1. Read online how easy it is to change rear brake pads on an Audi S4. Admire pictures some woman took of how she did it in "ten minutes per wheel" in her driveway one sunny day. Brag to friend who installed a new car stereo himself how easy it is to work on disc brakes. You are truly a DIY car stud because you have read how to do this.

2. Research brake pads. No big brake kit upgrades are planned right now, so decide on relatively inexpensive, but slightly better-than-OEM, Mintex "Red Box" pads due to their reportedly low levels of brake dust at equal or better to OEM performance. Go to purems.com. Notice that they sell these clever little rubber pads for jacks and jack stands to protect the undercoating on the car. They're much more clever than little wooden blocks, so include a set with your brake pad order. Brake pads plus jack pads come to something like 60 bucks.

3. A special tool is needed to turn the rear caliper pistons while compressing them. ECSTuning.com carries a relatively cheap kit on sale for 45 bucks. It's nice to have an inventory of good tools, so decide to pull the trigger and buy a kit.

4. Wait for packages to arrive. It's like Christmas!

5. Procrastinate so you're pushing the limit on your New York State inspection sticker. Even though the pads aren't completely shot, you'd like to avoid having the garage doing the inspection possibly require that you have them put on new pads to get the sticker. So, start the brake job with four days left on the inspection. Waiting until the last minute is fun!

6. Jack up left rear of car and put on a jack stand. The jack stand pad works great but the pad for the jack is completely retarded and would put pressure in wrong spots around the pinch weld. Place package aside with intent of returning it to get the $20 back. Go back to using a thin wooden block. Chock front wheels to be safe, just in case.

7. Remove rear wheel.

8. Make sure parking brake is off. It's hard to replace the pads when they're pressed firmly to the rotor.

9. Look around in wheel well. Notice little bits of rust starting here and there. Sigh. Realize once again that living in Central New York in the winter sucks. Add a line on the project list to get some Rust Bullet and coat everything in sight. It'll be a time-consuming job to do it right, but worth it in the long run.

10. Have a wire coat hanger handy, and grab your camera to get some pictures to make the blog look more interesting to attract a third reader or fourth if you're lucky.

11. Remove caliper bolts with 13mm wrench. A thin 15mm wrench is necessary to hold the nuts attached to the rubber boots still. A bicycle cone wrench works great. Note how your two big hobbies come together in serendipity.

12. Remove caliper. It slides right off the rotor. The pads may stay on the rotor or come off with the caliper.

13. Hang caliper on bent coat hanger from suspension linkages above to make sure the weight of the caliper doesn't put any pressure on the brake lines.

14. Remove old pads and set aside.


15. Insert special caliper compression tool with the right size end and unscrew it so the back presses firmly against the inside of the outer caliper.

16. On recommendation from audiworld.com posts, clean cap on brake reservoir and partially remove it to make it easier to compress the piston.

17. Attempt to turn handle. Fail. Note how little handle on tool seems far too small to get any leverage. Try several times, eventually stopping because hands hurt and you haven't made any progress.

18. Go back into house and wash hands. Hop on the computer to search Audiworld forum. Find post where some guy had the same problem and simply removed the disc to provide space for the tool and then remounted the caliper so he could get more leverage. Happen upon a web page with more details about the Mintex Red Box pads you bought. Read about how they're not recommended to be used with worn rotors because they won't seat as well as softer organic pads. You should use them only with new rotors. Swear. Decide to try them anyway.

19. Go back to garage. Attempt to remove disc. Notice that disc cannot be removed without first removing the caliper mount. Find two 8mm hex bolts holding caliper mount on.

20. Grab 8mm allen wrench from bicycle tool box (again, serendipity!) and attempt to remove bolts. Tap wrench with block of wood, then hammer. Note that only thing that happens is that tool gets rounded slightly. Swear. Put apparently inferior allen wrench away.

21. Grab 8mm socket driver and breaker bar. See how breaker bar doesn't fit into area necessary to get to bolts.

22. Put 8mm driver on ratchet wrench. Attempt to remove bolts. Hit wrench with wood and hammer. Note how it doesn't budge.

23. Go into basement in search of length of pipe to put over little tiny handle on tool to gain more torque. Wonder why handle is so small on the caliper tool and why so many people said this was really easy to do. Wonder if you're doing something wrong. Wonder if caliper is bad. Assume caliper is fine since it was working well before this.

24. Find long pipe previous house owners left and grab a hacksaw. Start cutting a shorter piece off. Rest forearm halfway through after several minutes. Wipe sweat from brow. Continue until complete. Make note to buy a new hacksaw blade to replace your dull one.

25. You have cut through metal. Go back to garage carrying the new "torque pipe" triumphantly.

26. Place pipe over ratchet wrench handle and attempt to loosen the 8mm bolts. Fail again. Put Liquid Wrench on list of items to pick up at hardware store and forget about removing the disc and remounting the caliper for leverage.

27. Wonder if piston tool is binding on threads because it's too tight against the caliper. Loosen it a little and try again. Fail.

28. Spray some WD40 on the piston and boot to try to make sure the rubber doesn't rip and ruin everything. Wait for WD40 to soak in a bit. Wipe off excess. Try again to turn the tool. Fail. Note again how thumbs hurt. Swear.

29. Grab newly minted torque pipe and put it over the little tool handle. Attempt to turn handle. Notice that the caliper turned a little. It's working!

30. Now that the piston has turned almost a complete turn, check the brake fluid reservoir to see if you need to siphon any off because it's being pushed up. Nothing yet.

31. Grab pipe and continue turning. Be surprised how suddenly it becomes easy to turn the tool handle. Note however, that the piston is not turning.

32. Remove tool from caliper and hear little clinking sound as sheared-off shear pin falls out of the tool. Sigh, then swear, more loudly this time.

33. Reassemble everything with the old brake pads so you can at least drive the car if you need to. Tighten reservoir cap. Note that the caliper bolts obviously had blue lock-tite on the threads. Make a note to pick up some lock-tite for the next brake pad change attempt.

34. Drive around carefully to test brakes. Everything is working fine. Give up for evening.

35. Do some more research on Audiworld.com. Read how most people have had luck with a special tool rented from Auto Zone. Regret not having read about the tool rental before having bought one. Read about opening the bleeder valve to relieve fluid pressure.

36. Fashion yourself a receptacle for bleeding brake fluid. Use a 1/4" length of tubing and punch a hole through the cap of a clean glass jar to receive the other end of the tubing. An obsessively cleaned Vlassic pickle jar to works well.

37. At next opportunity to work on car, jack it up onto the stand, remove wheel, remove caliper, loosen reservoir cap, etc...

38. Remove bleeder screw rubber dust cap. Put tubing over bleeder screw. Attempt to open valve with 9mm wrench. Fail. Try 10mm. Fail. Grab next wrench in set. Note that it's too big. It's a 12mm. Wonder why there is no 11mm wrench included in the set you purchased when you changed the spark plugs and needed the 10mm.

39. Find 11mm socket and remove tube. Wonder what will happen when you loosen valve without tube attached. Put 11mm socket on valve. Realize it's not deep enough to cover nut fully over the valve nipple. Swear.

40. Find little English measurement wrench that fits "pretty" well. Try to open valve. See how the wrongly sized wrench begins to mar the valve without budging it. Put wrong wrench away and give yourself a dope slap for not using the right tool.

41. Go weed and mulch the garden because that's apparently all you're capable of doing.

42. Go shopping for a deep 11mm socket. It's crazy to buy an individual one for $4 when a set of ten costs only $20, so plunk down a 20 dollar bill.

43. At next opportunity to work on the car for a couple hours, go back into barn and hit the unlock button on the key remote. Notice that nothing happens. Note that the little red alarm light is not blinking. WTF? The battery is completely dead. Strain to think of what you've done that could possibly result in a dead battery. There is nothing. Wonder why the h*ll a battery that's only two years old from the dealer would be dead. Realize that since the car is no longer covered under warranty and road-side assistance like it was when the original battery went dead two years ago, the only option to start the car where it sits is to charge the battery, get an emergency rechargable jumper kit, or replace the battery yourself. Swear.

44. Ignore battery problems for now and loosen bleeder screw with the new 11mm socket. It works, but barely moves, and is very hard to turn. Fluid starts to seep out, so quickly remove the tool and stick the tube back on the valve. Do not get brake fluid on any painted surfaces. It will reportedly de-paint things quickly.

45. Stick a series of shear pin replacements including small nails, bolts, pieces of wire clothes hanger, etc. into the special tool and repeatedly attempt to compress the caliper piston. Fail each time, shearing off whatever you've stuck in there.

46. Tighten the bleeder valve and put the removed brake fluid back in the reservoir. Brake fluid absorbs moisture from the air, so you don't want it sitting around in the open. Hope that you're not doing something that will screw up your brake system internals.

47. Wonder if you just haven't opened the bleeder valve enough to really relieve the pressure. Drive to the hardware store, in the other car. Grab a $4 11mm wrench so you can open the bleeder valve farther while the tube is on it after starting it with the deep socket you bought earlier. Grab a $50 emergency jump-it 12V kit to start the car. It comes with a light and a DC output jack, so it'll be useful for emergencies anyway.

48. Re-open bleeder valve with socket and put tube on it. Attempt to open it further with wrench. It's hard to get the angle right and the wrench is too short to get good leverage, so... Fail. Loosen valve with socket, ignoring brake fluid. Just clean up well.

49. Pump brakes a couple times "to relieve pressure" as described on Audiworld.com. Notice more brake fluid coming out.

50. Shear off another series of bits in the special tool while still failing to compress the piston.

51. Drive in the other car to Auto Zone to rent a new special piston tool. While there, pick up a $5 bottle of DOT 4 brake fluid just in case and a $4 can of Liquid Wrench. Smile when you find out that the tool "rental" is essentially free. You "buy" the $98 tool set, but get all your money back when you return it. Wipe the smile off your face by remembering you have already paid $45 for a now-busted tool rather than using this free one in the first place.

52. Before leaving Auto Zone, open the rental tool kit. Notice first how the special tool looks exactly like the one you bought, right down to the broken pin. Take some level of satisfaction in knowing there's at least one other person out there who was unable to compress their caliper piston. Go back into Auto Zone and exchange kit for a working one.

53. Go back home and try to compress the piston with the new tool, and with the bleeder screw opened up farther than before. Fail. Put the torque pipe on the little handle on the tool and give it another try. Try to remember how much force it took to shear off the pin in your other tool and apply force just short of that. Fail to budge the piston.

54. Swear a blue streak, then hang your head in a dejected fashion. Sarcastically congratulate yourself that you've now managed to spend $138 on tools and parts plus $98 that you can get back when you return the Auto Zone tool in order to save money having a professional do the job. Note you haven't included the $50 for the battery jumper since that's an unrelated problem.

55. Tighten bleeder valve. Look in shop manual and online for torque specifications for bleeder value. Fail to find them. Decide "good and tight" is okay. Reassemble brakes using old pads. Press on brake pedal and note that it's good and hard, and no fluid is coming from the bleeder valve.

56. Put wheel back on car, lower it, then get wife to turn the key while you attach the emergency jumper kit.

57. Drive around for a while to charge the battery while keeping an eye peeled for police due to the now-expired NYS inspection sticker.

58. Go back to weeding and mulching your stupid garden.

59. Find that two days later, the battery is again too dead to start the car.

60. Call and make an appointment for a brake pad change, a new battery, and a NYS inspection.

61. Stare at the pile of aftermarket parts in your attic waiting to be installed. They once represented a budding new hobby and hours of fun, but now they look just like a huge patch of thorny brambles that need to be dealt with.

62. Write down each step you've taken, trying to add a humorous tone, so you can post it on your stupid blog in an attempt for catharsis.