: CTS brake pad/rotor change procedure

11-20-06, 09:45 AM
Okay, so now that I am back and up on my feet again I can start doing these articles once more. This was SUPPOSED to be out on friday but I couldnt find the cable for the ruddy camera. Damn.
Anyway, lets get on with this weeks article:
"Your brakes and you"

Are your brakes squeaking? grinding? Have you taken it to Midas and been told "Oh yeah.. you need new brakes and rotors and a caliper and thats gonna be like 1200 bucks.." well blow that.
Lets cover how to do your brakes in your very own home with simple hand tools.
What you will need:
A floor jack, sure you can use the one in the trunk.. but are you really going to trust it to hold your car up for an extended period of time when it only cost GM about 5 bucks?
A socket and wrench set. If you are going to start doing stuff on your car you better get a tool set anyway.
In this case you need a size umm 13 or 17... I cant recall right now. Lets say a size 17. You will need the socket and a wrench too, I will tell you later.
A good sized C clamp or two.. Good sized meaning "can get around the caliper"
Your new pads/ rotors.
In the case of the CTS if you are replacing the rotors you will also need an Alan wrench set.

okay, lets go through this. first loosen the lugs, then jack up the car, then take off the lugs and remove the tire. you should see something like this:
Aww now isnt that pretty. Okay, its pretty ugly..
Now what we do is remove the caliper bolts, You can see one at the top of the caliper in the above photo, there is another on the bottom. On the CTS they are actually pretty easy to get to but there is a hitch.
Between the caliper and the caliper bracket there is a matching Nut that will spin if you dont put a wrench on it. This is nice, it prevents the caliper bolt from coming out during heavy use of the car.
Go ahead and use your two tools to remove the bolts, they are a little bit of a pain but are not all that hard to get out.
Now, if you are going to be doing the rotors I highly recommend a small stool or a hook to hang the caliper from to prevent stress on the brake lines, you really dont want to pull one of those buggers free.
Okay, so now you have the Caliper off you will see this:
the pads simply pull out (in this case they pull side ways, no big deal when taking them out and installing) You will see in the above photo my new pad, its a duralast Gold with lifetime warranty from autozone. Why did I pick these you say? Well.. they are 38 bucks for the set.. and are pretty good, and I will upgrade to ceramics later when I 1). get a bit more money, 2) upgrade the rotors since these are about half way through their lives. For normal to spirited driving these brakes are just fine (non organic semi metallic).
If you needed to change out the rotors just remove the two bolts for the caliper brackets and the alan screws in the rotor in itself, pull off the old rotor, put on the new one, reverse, done)

and Now on to the messy part. To reinstall the calipers you need to compress the pistons back down. to do this I usually use the old brake pad as a back plate then take the C clamps and slowly and evenly screw them down till the piston are flush with the housing.
In my case I was a little ambitious so I took off the brake bleed nipples before I compressed the pistons.
Whats the point you say? Well the brake fluid in the pistons was Black and disgusting. I drained it off into a cup (as you compress the pistons the fluid will come out the bleeder nipple) like so:
The fluid really was nasty but only in the pistons, after a bit of the black stuff it came out clear again. No biggie, I usuall keep a bottle of DOT 3 Brake fluid in my garage. The problem is that our fuild doesnt really cylce or anything, the stuff in the psitons has been there a while and the older, dirtier stuff will compress more making your brake pedal feel mushy. This is a short "top off " procedure but is by no means a complete brake fluid flush.
Anyway compress the pistons till they are flush with the housing, like this:
Its at this point that you can reinstall the caliper onto the caliper braket/hub assembly.
Its pretty straight forward after this, repeat this on the other side.
Put the wheels back on and lower the car. Get in the car and put the key in the Accessory position, try your brakes.. oh dear god you have you brakes!!... just kidding, pump them a few times and the pressure should come back.
(Special note, if you are bleeding them a bit its a good idea to test the brakes while the car is up, in case you get some air in the pistons you will have to open the bleeders a bit to let the air out, otherwise your brakes will be very mushy)
Congrats, you just did your brakes.

the rear caliper bolt size is a 15.

the rear brakes wear about half as fast as the fronts.
The front caliper is HUGE for a car this size.
This is the first car I have played with where the rotors are held on with alan screws.
This procedure should take about 1 to 2 hours tops if you are taking your time.

You dont need to bleed the brakes at all, but you do NEED to compress the pistons in the caliper otherwise it wont go back on.

Happy Braking,


(make with the rep points :) )

12-15-06, 10:41 AM
Thanks, and by the way are those brake pads from autozone?

12-16-06, 08:47 AM
Here are a few things to keep in mind:

1. There is no need to "remove" the bleeder screws, just loosen them a little bit to let the fluid come out, and don't leave them open too long or you'll drain the master cylinder, if that happens you have air in the system and now it needs to be properly bled.

2. The "black stuff" in the calipers is just old fluid that has absorbed some coloring and small particles of the seals inside the caliper. It's normal, it shouldn't really cause any "squishiness" and yes, it's a great idea to get it out.

3. Be sure to top off the brake fluid as mentioned with DOT 3 fluid, don't get fancy and use another kind or you'll end up ruining your brake system.

4. You can use the C-clamp method BEFORE you remove the caliper. Just open the bleed screw and put the clamp(s) over the outside of the caliper to run in the pistons. It can be done either way but if you do it before you take the caliper off you don't have to fumble around with all those parts. Note that sometimes, depending on how worn the pads are , this may not push the pistons in all the way so you may have to do a little more pushing in later.

5. Only remove the lower bolt on the caliper. Then swing the caliper up using the upper bolt as a pivot point. There are a couple of reasons for this but one is that it makes it easier to push in the pistons if you still have to do so, another is that the factory pad kit comes with 2 new bolts, one for each side. Technically you shold not reuse the caliper retaining bolts but most aftermarket kits don't come with them. If you must reuse the bolts then follow these instructions:

Important: If reusing the lower caliper pin bolt, the threads of the lower caliper pin bolt and the threads of the caliper bracket mounting holes must be free of residue and debris prior to application of threadlocker in order to ensure proper adhesion and fastener retention.

If reusing the caliper pin bolts prepare the bolt and the threaded hole for assembly:
• Thoroughly clean the residue from the bolt threads by using denatured alcohol or equivalent and allow to dry.

• Thoroughly clean the residue from the threaded holes by using denatured alcohol or equivalent and allow to dry.

Apply threadlocker GM P/N 12345493 (Canadian P/N 10953488), or equivalent to 2 /3 of the threaded length of the lower caliper pin bolt. Ensure that there are no gaps in the threadlocker along the length of the filled area of the bolt.
Allow the threadlocker to cure approximately 10 minutes before installation.
Apply a thin coat of high temperature silicone lube to the front brake caliper guide pin.

6. Finally, always be sure to torque the fasteners you removed to specification. In this case it would be 46 lb. ft. for the front and 44 lb. ft. for the rear.

Pump the brake pedal several times before attempting to move the vehicle!
If you don't then the brakes won't work when you go to move the car.
Then make sure the fluid level is correct and follow manufacturer instructions for pad break in.

Thanks to Kael for taking the time to make some pictorial instructions.

12-21-06, 11:17 PM
OK good write up but let me add some professional advice and points here.
One thing you should think about is if the rotors are thick enough it is much better to find a local shop to turn your rotors on car as this will allow for the run out in the hubs also.
A big thing to note is unlike what was said the black crud IS going to cause pedal problems if left to accumulate.
Another point I must make is that brake fluid is HYGROSCOPIC which it means it absorbs moisture and can even pull it from around the seals and gaskets and THRU the hoses.
Now this is very minute but it does occur. Another thing is that because of the HYGROSCOPIC qualities if you have one drop of water it mixes with ALL of the fluid in the system and can reduce boiling points and cause spongyness.
So before you ever start this open the master cylinder cap after cleaning around it, suck all of the fluid out of the master cylinder, even down to the little round cavities and wipe out all of the black crud too.
Then fill it back up with either dot 3 or dot 4 brake fl;uid, then as you are doing your brakes you can use clear vinyl tubing , open the bleeders (you can free up corroded bleeders by taping the area around the bleeder like removing tie rods/ball joints) and let the brake fluid flow and push the pistons back in while its open too.
Then let it flow for a few minutes, keeping the master cylinder full and geting clear fluid to each wheel ,therears take longer but a quart of fluid is cheap and it does keep the corrosion to a minimum.
A good thing to do is pick upo extra slicone brake caliper lube while doing this and the now prefered method of squeak reduction is to simply rub a thin coat of silicone grease on the back of the pads (after applying any stick on anti squeek shims that come with the pads) and make sure they are a snug but not tight fit in the caliper brackets and then clean out the slide holes on most brakes and relube the pins(if used) and sleeves and make sure they slide free. And lightly lube any point where the calipers,pads,brackets meet.
I like to also apply the brakes to getthe pads out againts the rotors before test driving and then re open the bleeders to help move out more brake crud and debris.
I do this everytime I do a brake job and Iam a Certified master technician and do many brakes every day and really have very few comebacks and infact I am the guy who gets the squeek/squeal/complaints when they comeback even though I am not the original tech. And all of the ones that come back are either using the blue pad antisqueal spray or are not lubricated properly ( a big problem with PBR type brakes).
See one thing I found out a long time ago was when I worked for a fella who had ran a Shell station for years , he had both Shell and the old Texaco lube service manual they put out so as to give the mechanics a proper database to go to for cars requirements(ie when to change/service or what to change/service on each car) and one of the things done during service was to up end a can of brake fluid on the master cylinder and as the oil was being changed they opened the bleeders on the brakes, And then adjust brakes shoes out (the adjustments went away as self adjusting brakes came on the scene and disc brakes). This always made customer fell good and made cars safer as they actually got service not a drop the oil plug ,screw on the filter and top up the fluids for 29.99 by 3 or 4 guys who most likely couldnt adjust brakes on a drum brake car!
Good luck and if anyone has a brake question give me shout at Xanadu4024@aol.com as i still cant send PMs.
Lee Abel

09-23-11, 07:16 AM
Thanks for the clear instructions!! This was my first time with a brake change on my wife's 2006 CTS and it was a snap!!
The dealer wanted over $200 but is only cost me $28 and one hour of time. Wow... That's money in the bank!!

02-28-12, 02:20 AM
Not sure which thread I should bump but I pick this one. Anyway, I'm planning on changing the brake fluid in the car and some people espouse the gravity method. Does it work with this car (e.g. is the master cyl high enough) and how long does each corner usually take?