2006 GMC Sierra, 5.3, 4WD, Rear Brake Shoes (Single Spring Application)

This 2006 GMC Sierra 5.3, 4WD, came into the shop for its 100,000 mile maintenance. We replaced the spark plugs, wires and air cleaner element. We also added oil to the front and rear differentials.

Another service we performed was an all-around brake job. We replaced the front brake pads and the rear brake shoes. We also had the front rotors and rear drums resurfaced at a machine shop.

In this post, I will concentrate on the rear brake shoes. These have a single spring application. They are known to be a bit of a problem. Many techs and DIYers complain about this setup. I will show you a few things I have learned from doing them.

In the two pictures below, you will see the single spring. It looks something like a horseshoe and has a lot of pressure on it. They do make a special tool just for pulling this spring back and removing the brake shoes. I did not use the tool on this job. It is possible to do the job without the expense of the special tool. However, caution is advised, as the spring is very tight.

In the picture below, you will see one of the brake shoes. On this application, the whole apparatus is replaced. When you purchase the new brake shoes, it will come with the shoe and the parking brake lever attached. All of it comes off and is replaced, unlike on other applications where you simply remove a keeper and the parking brake lever remains on the vehicle. 

Removing the cable from inside the spring going to the parking brake lever can be troublesome. In the picture below, you will see the new brake shoe (parking brake lever and spring conduit attached). The parking brake cable goes through the spring conduit and hooks to the parking brake lever. Again, this is the part that many people find very frustrating.

To make this much easier here is what I do: first, (on this model with extended cab), I look below the back of the extended cab on the frame. In that area is the connector for the front cable coming from the parking brake to the two rear cables each going to one side respectively. Below you will see the area and then a picture of the connector on the frame:

Once the connector is located, I detach one (or you can do both at the same time) of the rear cables. See the picture below:

I can actually detach it just using my hands, so it is not that hard to do. I believe the top cable goes to the right (passenger) side and the bottom one goes to the left (driver) side. Once the rear cable is detached from the connector, I now have slack on the other end (the brake shoe end) to move the cable in and out easier. See the picture below:

There is a tab on the end of the spring conduit that must be pressed down to allow the cable to slip out of the spring. Sometimes the cable will come out of its own accord once I detach the connector. Now the brake shoe (with parking brake lever) will slide right off the parking brake cable. See the pictures below:

To remove the shoes themselves (without the special tool) I simply use a large screwdriver, pliers and a pair of side-cutters. There is an adjusting spring to remove, along with the adjuster.

I always grease the contact points to make for a nice, smooth and quiet braking experience. I use caliper grease on the rear brakes and front as well. See the picture below:

I also make sure to clean up all hardware with a good quality brake cleaner.

Once the job is done, I always torque the lug nuts to specification.

I torqued all four wheels to spec and then test drove the vehicle. All was well. The brakes felt good and smooth and the parking brake worked smoothly as well. We shipped this one to the customer. Another one fixed.

2003 Chevrolet Silverado 5.3, Brake Lights Illuminated and Blower Motor is Inoperative.

This 2003 Chevrolet Silverado 5.3 came into the shop with several customer concerns.  The major concern was that the AC was inoperative.  He mentioned the AC had stopped working within the last two weeks or so and (another concern he had) his brake lights (both the ABS and red brake light) had come on at the same, or about the same time.

First things first, I confirmed the customer's concern.  With the AC on (the control panel lights were on and showing the AC was on), going down the road, cold air would blow in.  When you stopped the vehicle, no air at all.  The brake lights also were illuminated in the panel as the customer said.

Next thing, pull out a wiring schematic and do some checking on the circuit.  It was obvious from driving the vehicle down the road (and observing it visually) the AC clutch was working and the compressor was cycling.

Since the blower motor resistor was fairly easy to access, I started there.  With a test light I checked for power on the respective wires to the resistor.  The Power Probe showed no power on any wire at any speed.  The feed wire also showed no power.

(This is why it is important to "test and not guess".  I have seen a lot of people just throw a resistor in there, because they "go out all the time" only to have it not work.  Make sure you know the cause of the problem before you start removing and replacing parts.  R&R of parts can cost you a lot of time and money.  The best solution is to take it to a professional and get it done right the first time.)

Next, I went to the fuse panel in the left side of the dash.

No power at the fuses.

The brake fuse and HVAC fuse are supplied power by the ignition switch.  An orange wire supplies voltage to these fuses.  Probing this wire, as expected, I found no voltage.

It was time to replace the ignition switch.  The ignition switch is an electrical component.  It is not the part you put the key in to start the vehicle . . . that part is the key and cylinder or tumbler.  Some ignition switches will come with a wiring harness.  This one did not.

To access the switch, remove the steering covers and the tilt handle.  To remove the handle pull outward.  Sometimes a pry bar or long screwdriver may be necessary.  Just be sure not to break any of the plastic surrounding it.

The switch is located on the bottom of the steering column.  It is located just below the lock cylinder.

Disconnect the holding tabs (2 white tabs, one on each side) and gently pull down.  Next remove the wiring harness.  The switch by itself is shown from a couple of angles below.

Once the switch was replaced and installation was completed, it was time to try out the AC and see if the brake lights were now off in the dash.  Sure enough, the brake lights were no longer illuminated and the blower motor was now operational.

The high speed was inoperative, but the customer said it had been so for several years and declined to have it repaired.

1998 Chevrolet S10 2.2, Brake Lights Not Working

This vehicle came into the shop with a customer concern of no working brake lights.  The vehicle had been taken to another repair shop a few weeks ago and the customer was told it would cost several hundred dollars to repair the problem.

I confirmed that all three brake lights were inoperative.  This model has the customary two brake lights on the rear and a brake light called the Center High Mount Stop Light, or CHMSL for short.  All three brake lights were inoperative. (After doing some further investigation after I repaired the truck, I found the CHMSL bulbs were blown.)

This led me to a quick look at a wiring diagram, which led me to take a look at the Underhood Fuse Panel.

When I removed the cover something caught my eye, even before I could check any fuses.  I noticed something was missing.  Where I am pointing you will notice four empty cavities.  This is where the CHMSL Relay is suppose to be . . .  but it's not!  The relay would look like the relay above my finger (the grey rectangle).

I happened to have one in the shop.  I plugged it in.  Below I am pointing to the now present CHMSL Relay.

Sure enough, with a quick test of the brake pedal . . . presto!  the brake lights were working.

This is a quick post just to remind us not to overlook the small things.  Before pulling out the PowerProbe or Test light or whatever else, be sure to give a visual inspection of the components.  As this job reminds us, first make sure they are where they are suppose to be; and second, make sure they are in good/working condition.

Sometimes the easy, simple solution is the right one.