New front brakes on a full-size GM truck or SUV.
New Front Brakes:

Replacing Front Brake Pads On A
1996 GMC Yukon Or
Chevy Tahoe/Suburban

May Also Apply To GM Full-Size Pickup Trucks

 

In This Article:

Front brake calipers are removed by removing the slide pins. New brake pads are installed on the caliper. The caliper is re-installed with new slide pins.

Related Articles:

Skill Level: 3 (Intermediate) Time Taken: About 2 Hours

By Bruce W. Maki, Editor

Start:

My 1996 GMC Yukon has about 160,000 miles on it. I was planning to drive from my home in Northern Michigan to southern Florida, pulling a trailer. I bought this truck a year ago, and I hadn't yet done a brake inspection. When I raised the truck up and took the wheels off, I realized that I needed to replace the brake linings front and rear.

GM truck with front wheels removed.

After I had raised the truck and placed it securely on jack stands, I removed the wheels.

 

Note how close the brake pad metal backing is to the rotor. These pads were really worn down.

Worn-down front brake linings.

 

Turning the steering wheel to access the front brakes, GM truck.

The brake caliper is held secure by removable slide pins (also called guide pins).

I turned the steering wheel to expose the back side of the front disc brake unit.

 

GM Full-Size Truck -
Front Brake Slide Pin Locations:

This is a rear view of the right-hand (passenger side) front brake assembly.

The red arrows point to the slide pins (sometimes called guide pins). The brake caliper slides back-and-forth on these pins.

Guide pin locations on front disc brakes, GM full-sized truck.

 

3/8" Allen socket too used to remove brake slide pins, GM. To remove the caliper slide pins, I used this 3/8" Allen socket.

 

I used the Allen tool and a ratchet to remove the slide pins.

Before doing this, I cleaned the dirt from the hex socket in the head of the slide pin, using a small flat screwdriver. I also sprayed some silicone into the fastener head, because the Allen socket fit so tightly. I used a small hammer to tap the Allen socket into the head of the slide pin.

Removing caliper slide pins, GM.

 

Caliper slide pins after removal.

When I first removed these pins, I was confused for a minute because I couldn't see any threads sticking out (top pin). I thought I had broken the slide pin and left the threaded section stuck in the steering knuckle.

Then I discovered that the smooth body of the pin is actually a separate piece. After tapping lightly, the sleeve moved back and exposed the threads of the slide pin (bottom pin).

 

Pushing Back The Brake Caliper:

The red arrows indicate how far the caliper piston was sticking out. The piston needs to be pushed back before the new pads are installed. Brake caliper piston before replacing pads.

 

C-clamp used to push brake caliper piston back. I placed a 6-inch C-clamp around the caliper (it barely fit) so the clamp was pressing on the outboard brake pad.

 

One Small Problem:

There are metal spring-clips on the outboard pad. Before I could push the caliper piston back, I bent these clips outward so they wouldn't interfere with the pads moving back.

Bending back brake pad retaining clips, GM truck.

 

Brake caliper piston after being pushed back with clamp.

I slowly tightened the C-clamp to push the piston back.

Note how afterwards the piston was barely sticking out (red arrows).

 

I removed the cap on the brake fluid reservoir to check the level. The level was about 3/4" lower before I started this job (I had already replaced the pads on the other wheel).

If the reservoir had been topped up, it's possible that brake fluid would have overflowed and dripped all over the place. Sometimes it's necessary to remove some fluid using a turkey baster or some other siphoning device.

Brake fluid reservoir.

 

Supporting the brake caliper during repair or pad replacement.

I slid the caliper (red arrow) off sideways and supported it with a bungee cord.

DO NOT let the caliper hang by the flexible brake hose... this can damage the hose and cause a brake fluid leak, which can cause a sudden loss of braking ability.

 

Once the caliper was removed, the rotor just slipped off the hub. Removing front brake rotor or disc.

 

A Quick And Cheap Fix For
Rotors In Fair-To-Good Condition:

Brake rotor in fair condition.

The rotors were still in decent condition.

There was a small ring of rusty metal around the outer and inner edges of the rotor surface.

 

There was a slight ridge along the inner rim of the inboard side of the rotor. I could see light under the ruler (look between the 15 and 16mm marks), which indicated a raised surface at the inside edge of the shiny rotor surface. Checking rotor surface for high spots.

I've seen lots of people simply re-use rotors like this without turning them or doing anything to the surfaces. If the new brake pads are exactly the same size as the previous pads, they will probably not ride against those raised rusty rings at the inner and outer edges. If the new pads were just slightly wider, then they won't fully contact the rotor until corresponding grooves have been worn into the new pads.

Instead of simply re-using the rotors, I prefer to clean them up and remove the "glaze" (shininess) on the rotor surfaces. My auto mechanics instructor insisted that new brake pads used on shiny, glazed rotors really don't work to their fullest potential, so removing the glaze is important when installing new pads.

Grinding small rust ridge from edge of brake rotor. I used an angle grinder to carefully grind down the rusty strips and the small ridge.

 

Then I used a random orbital sander with a 40 grit sanding disc to clean up the surfaces of the rotor.

After sanding with 40 grit, I sanded the rotors again with 60 grit. The sandpaper disn't last long... I used one sanding disc of each grit for each rotor face.

Removing rotor surface glaze with power sander.

 

Rotor surface after sanding.

After sanding, there were some small rusty spots on the inboard side of the rotor.

I'm not sure what causes these spots... it might be from overheating. I've seen much bigger spots like these, with a blue color that iron and steel get when they become very hot, and those spots eventually flaked off large chunks of rusted metal.

I'll have to check these rotors a couple of times a year to make sure the spots don't get worse.

 

The outboard side had no spots.

The metal was pretty smooth after sanding, with a dull satin-like finish.

Brake rotor surface after sanding.

 

Rotors - Replace, Turn, Or Quick Refinishing:

The method of refinishing rotors shown here is not the best approach when replacing front brakes. My method is a CHEAP FIX, and should only be done if the rotors are mostly smooth and free of large overheated spots.

Most auto parts stores can "turn" rotors on a brake lathe for about $10 to $15 per rotor. The list price for these rotors at my local NAPA store is about $54 each, though your actual price may be lower. New rotors are necessary if the rotors have worn down to a thickness where turning will make them too thin. If the rotors are too thin they will overheat and warp, which will create a pulsation in the brake pedal.

For best results, rotors should be turned or replaced.

 

Preparing The Sliding Surfaces:

Cleaning rust from sliding ways on steering knuckle, GM truck.

I used a die grinder and a coarse Roloc disc to clean up the sliding surfaces on the steering knuckle.

I used to use a file to clean these surfaces, but a die grinder is much faster and easier.

 

I also cleaned the sliding surfaces on the caliper. Sliding surface on front brake caliper, GM truck.

 

Installing New Brake Pads:

Installing new brake pad in caliper, GM full-size truck.

I had to unhook the bungee cord to install the new inboard brake pad.

There is a pair of spring clips on these pads, so I squeezed the clips and pushed them into the caliper piston.

Warning: Make sure your hands are clean when installing the new brake pads and rotor. Even a small amount of grease or oil on the surfaces can prevent the brakes from stopping the car properly.

After installing the inboard pad, I installed the outboard pad on the brake caliper, then I placed the rotor back on the hub and tried installing the caliper to see if it would fit.

Before actually installing the caliper, I applied a thin layer of copper-based anti-sieze compound to the sliding "ways" on the steering knuckle.

Anti-sieze applied to sliding ways on steering knuckle.

 

Anti-sieze applied to slide surface on brake caliper, GM.

I also applied some anti-sieze to the sliding surfaces on the caliper.

Then I set the caliper in place.

This anti-seize compound acts like a lubricant but will resist melting in the high temperatures reached during braking.

Be careful with lubricants around brakes! If any anti-seize gets on the brake pads it can reduce the braking ability... and it won't just "burn off" over time, it can soak into the friction material.

Any lubricant or oily substance on the rotors must be cleaned off with automotive brake parts cleaner.

 

I bought new caliper slide pins at my local NAPA store. The list price for these is $7.50 each, (NAPA part number 82792) and the truck needs a total of four. New guide pins for GM truck front brakes.

 

Silicone-based brake lube applied to caliper slide pins.

I applied some copper-based anti-sieze to the threads of the new slide pins, and I also applied a generous amount of Syl-Glyde brake lubricant to the outer parts of the slide pins.

Syl-Glyde is important to ensure that the brake caliper slides back-and-forth properly. Without this lubricant the caliper may eventually stick and one pad will wear faster than the other.

 

I inserted the slide pins and tightened them with the 3/8" Allen socket.

I read in my Chilton's manual that these pins are supposed to be tightened to 38 foot-pounds.

Installing guide pins to secure caliper, GM truck.

 

Finished front brake job, GMC Yukon or Chevy Tahoe/Suburban.

The completed brake job.

I replaced the wheels and took the truck for a test drive.

TIP: To prevent corrosion from causing the wheel to stick to the hub, I always apply a thin smear of white lithium grease to the hub. I also apply a small amount of grease to the wheel studs, which prevents them from rusting in place. I've been following this practice for over 15 years and I've never had difficulty removing a wheel or the lug nuts.

The list price for the brake pads (NAPA Part #TS-7259BM) was about $37, and the slide pins listed for $7.50 each.

The total list price for the parts shown here was around $67 (not including sales tax), though your actual price may be lower.

Warning:

After replacing brake pads, the linings may not be close enough to the rotor to actually grab. The result is a very low brake pedal the first time you hit the brakes... and possibly no ability to stop. I've heard of mechanics that backed a car out of the garage and promptly crashed into a parked car.

Before moving the vehicle, you MUST pump the brake pedal until it feels firm and normal. If the brake pedal won't become firm, then there could be other problems, such as parts intalled improperly or a brake fluid leak.

 

Another Warning:

In my mechanic's training, the instructors stressed the importance of braking gently until the new linings have been "broken in". The instruction we got was to make about 30 stops from moderate speeds (30 to 35 miles per hour) with only light-to-moderate pressure applied to the brake pedal. After that, you can slam on the brakes to impress your friends with your mechanic's skill.

Apparently, hitting the brakes too hard before the linings have broken in can cause overheating and damage to the linings.

Read our Disclaimer about brake repairs

More Info:

Tools Used:

  • Ratchet Wrench
  • Sockets: 3/8" Allen
  • C-Clamp, 6"
  • Pliers
  • Bungee Cord
  • Die Grinder With Roloc Disc (Or File)
  • Angle Grinder (Optional)
  • Random Orbital Sander (Optional)
  • Jack Stands
  • Floor Jack

Materials Used:

  • Brake Pads, NAPA Part #TS-7259BM
  • Brake Caliper Slide Pins, (4), NAPA Part #82792 (Sold In Pairs)
  • Sanding Discs, 40 Grit, 60 Grit
  • Roloc Disc, Coarse
  • Syl-Glyde Brake Lubricant, Or Equivalent
  • Copper-Based Anti-Sieze Compound
  • Automotive Brake Parts Cleaner

Related Articles:

 

 

 

 
 
 
 
 
 
 
 
 
 

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© Copyright 2009 Maki Media Group LLC

Written April 28, 2009