# Rear Truck Brakes



## Rubrhammer (Nov 27, 2006)

The main goal of this operation is the rust removal on the caliper mounting bracket. That in itself will help to free up the movement of the pads. I'll go into a lot of detail for the sake of the novices that may want to attempt this. Hopefully no one is offended and it isn't TOO wordy for you. The images are from a 2000 1500 Silverado.
This will apply to GM trucks, 99 and newer. I've done some Ford cars and their front brakes are similar in design though not exactly the same. I can only guess that the Ford and Dodge trucks will have similar designs while bolt sizes may vary and the clips may look different. Toyota also uses similar designs on their cars and I believe GM copied this design. So Tundra guys, this may apply to you also.
First you want to find a level place to do this job.
Then you want to get your wheel chocks from your trailer and block your front wheels.








While you're getting the chocks grab your torque wrench also.
Whether ½ or ¾ ton you'll need a lug wrench or a 7/8" socket for the lugs and I use a breaker bar. An air impact gun is nice and I have one but it is a cheap one and doesn't have near enough torque to break the lugs loose.








Crack the lugs loose before you jack up the truck, its easier at this point.
Jack up the truck and support it on jack stands.
Finish removing the lugs and remove the wheels.
I'm going to recommend doing one side at a time so you don't mix the pads left to right.
Now the fun begins.
Just a point to mention here, all threads are right hand, there may be times in the removal process that you don't believe it though.
Grab some safety glasses or goggles and wear them, there is a lot of grit and dirt under those wheel wells.
You'll need metric wrenches for this: ¾ ton guys, Torx T-55 MALE for the caliper(get it in a 3/8 drive socket), 18MM box wrench for the caliper bracket. I recommend a 6 point, 1/2" drive socket and 1/2" drive breaker bar to break them loose, but you can get by with an 18MM box which you WILL need. You will also find a ratcheting 18MM box wrench to be handy because there isn't enough room between the leaf spring and th caliper to use a ratchet,but there again not required.
½ ton guys will need a 12 MM box, either an 18MM box or an 18MM socket, ½" drive breaker bar and ratchet and possibly a 17MM open end wrench if the slider pins decide to spin on you.


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## Rubrhammer (Nov 27, 2006)

There you can see the 2 bracket bolts and one of the caliper bolts at the top.
The first thing I do is to loosen the caliper bolts. On the ½ ton you can remove the bolts and the caliper at this time. On the ¾ you can't remove the top bolt from the caliper until the bracket is removed but this is when you have leverage on the bolts so get them loose. There is a THREAD LOCKING COMPOUND on the threads of all the bolts that make them VERY tough to remove the first time so be prepared to have sore hands.
Next take out the bolts that hold the caliper mounting bracket to the rear end housing. 
You can now remove the caliper/bracket assembly from the rotor. With the assembly removed you can now remove the caliper bolts and take the caliper off of the bracket/pads assembly.
Find a place to hang or set the caliper so it doesn't hang from the hose, it should be able to rest on the leaf spring.
Time to get yourself some refreshment, getting those bolts out was a sweat generating job. ½ ton guys, you had it easy get back to work.
We'll start the inspection here.








This is what your braking surface should look like on both side of the rotor. These brakes and rotors have about 26,000 miles on them and been on for a couple of years.
Look at both sides of your rotors. Is there rust on the pad swept area? The rust might be light orange in color and dusty looking or it could be dark brown and a heavy scale. Are there ridges and grooves? If you have the heavy scale or deep ridges and grooves this just turned into a major job. You'll need to remove the rotors and either replace them or get them turned. If you do then you'll need to get new pads also. If you have rust of any sort, this indicates that the pads were not making good contact with the rotor.(unless the truck has set for a while and has surface rust or there is water splatter on a good brake surface) You'll know the difference when you see it.
Flip the caliper over and find the stainless clip that the top of the pads ride on.








This needs to be cleaned up some to look like this. You only need to clean the araea that the pads come in contact with.


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## Rubrhammer (Nov 27, 2006)

Take the bracket/pad assembly in hand and see if the pads slide freely on the stainless clips. Take note of which pad is inside and which is outside. If you lose track you can usually tell the inner by the circles on the back from the pistons. Look at how the pads are contained, there is a slot in the end of each pad that rides over a stainless clip, or there is a tab on each end of the pad that slides in a slot on the stainless clip. These features vary by model. Below (or above in the case of the 1500), the tab/ slot feature is usually a flat area that is also in contact with the pad. These are the areas that we are going to address, both on the pads,clips and ESPECIALLY the bracket.








Here you can see the contact areas highlighted with red. You can see how cruddy the clip is also.
















You can see the rust on the clip from the pad and the areas circled have scale built up on them.
As gnarly as these look, the pads were still free in the brackets and were causing me no problems.
Remove the pads by sliding them (or tapping with a hammer).
If you have a mounted wire wheel and are CAREFUL, you can clean up and almost polish the contact surfaces of the stainless pieces. (THIS IS TRICKY TO DO ON A MOUNTED WHEEL AND IF THE WHEEL CATCHES AN EDGE OF THE CLIP CAN SUCK THE CLIP AND YOUR HAND INTO THE WHEEL. DON'T WEAR GLOVES) If you don't have a mounted wheel, use a small wire wheel in your drill To do the job.


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## Rubrhammer (Nov 27, 2006)

Here is the back side of the clip prior to cleaning, notice the build up of scale on some of th surfaces.








This is the same surface after wire brushing with a small brush in an air grinder. You could use a Dremel tool or a drill to do the same thing. A hand brush will remove dirt but isn't very effective on the rust as it is imbedded in the stainless. Scotchbrite pads work to some extent.
With a small screw driver or needle nose pliers, remove a stainless clip. Do one at a time, some models they are not identical. On the 1500s they are interchangeable.
Clean the back side of the contact areas. This can be difficult, do the best you can. If the clips are deeply pitted in the areas that the pads slide on, feel free to replace the clips. This rough surface can trap water and rust the mating surfaces. It may also impede the pad travel.
OK, you've cleaned up the clip, now the bracket. This is thee most common cause of brake pad freezing. The contact areas on the bracket build up with scale BEHIND the clips and pinch the pad.








Sorry about the blur, another view of the scale.








Not a clcear pic but you get the idea, file it smooth.

Nice idea having stainless hardware that doesn't rust as your sliding surface BUT the rust is now hidden and just as big a problem.
Depending on how bad the scale is will dictate the removal method. At this point a vise is nice to hold the bracket. If its bad, use a welders chipping hammer or a small hammer and chisel. Don't go nuts on it, just chip the scale. Then grab a file and clean up all of the contact surfaces that the pad would ride on. If you're not sure which areas, grab a pad and put it in the bracket without the clip. Get ALL of the scale! Don't worry about getting rid of all the pits in the surface, though it doesn't hurt to get most of them. If you get rid of all the pits you'll slightly increase the clearance for the pad, not a bad thing but a lot of filing.
Repeat for the 2nd clip and its mounting area.
This step is optional. At the shop we don't do it but I will on my own to see if it lengthens the maintenance interval. Use some rust converter such as Extend or Permatex rust converter on the contact areas of the bracket. You can get the Permatex at Ace hardware in a spray can.








This is what I used, it converts the rust to some sort of polymer that inhibits further rusting. We'll see. I've used it in other applications and liked it. This area is subject to high heat though so I don't know if it will last.








This is what the treated areas look like within a few minutes.
If you do the treatment, do the bracket before the clips to give it a chance to dry. I brushed it on very lightly so as not to create a build up.
One last area to address on the caliper bracket. The slider pins.








Check their boots for tears. If they aren't intact then replace them. Use a brake lubricant on them, it is designed for the environment that it has to function in. You can get it at any auto parts store. Time to address the pads. If you are not changing them (and even if you are), check to see if they slide freely now in the bracket. Slip one end into the clip and swing the other end in. It should want to rotate right through to the center of the bracket and fall out. If there is a lot of drag (and this is a subjective feel) take the pad to the pedestal grinder and LIGHTLY radius the edges of the contact areas. If this doesn't free it up go back and grind(or file) the areas that can pinch or are pinched by the clips. If its tight now it will just get tighter later when the rust returns. We always do this on new pads also. We've found that the stampings on the pads usually have sharp edges that can dig into the clips.
The picsc of the pads are blurry but I'll include them, hopefully you get the idea from the shiny areas.








This is the pad as it came out of the bracket. They come painted or powder coated but they rust behind the coating. I used a file to put a small radius on the edges of all the surfaces that slide on the clip to eliminate the paosibility of them digging into the clip. I also filed off any scale or flaking paint from the contact surfaces. These are stamped plates and are rough to start with. Don't go nuts here either as you don't want TOO much clearance.
















This is also a good time to adjust the E-brake. This is a drum brake within the rotor. I don't know about you, but I use the parking brake most of the time. Mine needed adjusting as it wouldn't hold me if I was in gear. Getting the rotor off can by a bear because there is usually a ridge of rust built up on the outer edge of the drum and you have to get the brake shoe to compress enough to go through it. Mine came right off this time. There was a ridge but not a bad one and my brake needed adjusting so everything was in my favor. I used a carbide burr in my die grinder to remove the ridge before I put the rotor back on. You could use a sanding disc in a drill or a stone in a drill or Dremel tool.
As for adjusting, I took the adjustor wheel out about 3 turns on each wheel. I made sure the e-brake wasn't dragging and that the rotor went on easily. They work great now.
Reassemble. on the 1/2 ton, bracket first, pads in the bracket and then the caliper. Put the wheels on and snug up the lugs. let the truck down and torque to 140lb/ft. On the 3/4 ton you HAVE to assemble the caliper to the bracket BEFORE you mount the bracket. Ask me how I know.








140 lb/ft for the 3/4 on also. Get in and pump the brakes just to make sure they are up before you start the truck.

On a side note, the procedure is very similar for front brakes also be it on cars or trucks. The problem also exists on fronts as well. For example. Thursday I did all four corners on a 2005 Gran Prix with only 17,000 miles. All of the pads were hanging up to some degree. The rears worse than the fronts. The rotors all needed turning, the rears because of rust, the fronts because the outer pads were hung and the inners were doing all the work and had grooved the rotors.
Happy wrenching,
Bob


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## Carey (Mar 6, 2012)

Wow you guys get alot of rust... Incredible!

Our vehicles wouldnt have half that much in a 20 yr old vehicle.

Great post and you do good work!

Carey


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## Rubrhammer (Nov 27, 2006)

Thanks Carey,
You should have seen the rotors that came off of an 04 HD2500 last week, the scale was unbelievable and I had to drive the pads out of the bracket with a hammer!!
Bob


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## bigdisneydaddy (Oct 26, 2007)

I have done quite a few of these and yours looks about as good as any we get around here. The last 3/4 ton I did had only 22,000 miles on an 04 and it required all 4 rotors due to the rust scaling. Silicone brake lube is also a good idea on the slide pins since it holds up better. 
I know its not the safest way but I frequently have to use a cheater bar to get the screws loose. 
Great tutorial that will hopefully save some members some $$$$

Scott


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## azthroop (Jun 16, 2007)

I have always heard about this thing called, "rust", but have never seen it! Thanks for the education! We may not have rust in AZ, but we get dirt and sand everywhere you don't want it! You pretty much have to change your windshield every couple of years b/c it gets so pitted! That's where the glass insurance comes in handy.


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## Rubrhammer (Nov 27, 2006)

We have this thing called sand here also. Only here it is used on the paved roads in the winter to counteract something else foreign o you, snow and ice.
lol
Bob


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