How to remove front rotors on 1997 Suburban K2500?

Question

4x4. Already remove caliper, now I just can't figure out what to do next. Is the rotor screw in or what's holding it in place. Local auto parts guy said it should slide off?

Answer 1

I'm attempting to replace my rotors this weekend - on my 99 Suburban K2500 diesel, the hub and rotor are pressed together and held on the spindle via 4 bolts on the engine or inner side of the spindle (after removing the 35mm or 36mm axle nut). I don't know if this is true with your 1997. You have to remove these spindle bolts first (they can be an unbelievable pain - I'm still trying to get them off using gallons of penetrating oil and a impact gun) then the hub and rotor should come off together. You'll then need to press the wheel studs out of the hub and rotor to separate the two. Finally, you have to press the wheel studs into the new rotor and press the hub and new rotor asssembly together.

Hope that helps - it's a bigger pain than any other brake setup I think I've ever seen.

Answer 2

It should. Does yours have an 'auto' four wheel drive, controlled from within the unit? If so, remove the dust cover, cotter pin and nut that hold the rotor to the spindle. Tap rotor with a 'dead blow' hammer, then it will come off.Don't forget to support the truck with good jack stands or a heavy block of wood while you're working on it. Don't trust the jack, no matter how good it is.

1. Those two allen head cap screws that you can't see along side the cylinder are 3/8 inch. I fooled around with 7 and 9 mm metric wrenches for about 15 minutes until I decided to try my American sizes. I was positive these would be metric by now. They only have to be loosened until they are out of the threads they screw into. They do not have to be pulled all the way out. The rubber collar around them does not have to be touched.

2. The caliper assembly can be pulled out either by rotating the top out or by pulling straight out. A small prybar or the claw of a carpenter's hammer helps here. Make sure the caliper assembly does not hang by the brake hose. This can damage the hose.

While you're in there, check the hoses for cracks and check around the piston for brake fluid leaks. Fix anything you see.

3. Changing the pads themselves is pretty straight forward. The outer pad needed a big screwdriver to pry it off, the inner came out easy.

Remember to push the piston back in so that the new pads will clear the rotor. I did this after removing the outer pad. I used an 8 inch C clamp between the inner pad and the back of the brake piston. Give it a half turn at a time and it will go in pretty easy.

Make sure that if you have added any brake fluid over the life of the last set of pads that you check the master cylinder for overflowing.

If the pads don't go in pretty easy, something is not right. Take them off and try again. There are some fairly close fits in there for the pads and some holes and pegs for the outer pads.

4. At this point the rotor can be pulled off the studs and checked on both sides. I caught mine in time and there was no scoring or anything on the faces. I put it in as-is. The rotor is independent of the spindle and nothing else has to be pulled to remove it.

If the face of the rotor is scored or gouged or there is pulsing in the brakes, it should be turned or replaced to bring it back to specs.

5. I put two lug nuts on two wheel studs to hold the rotor in place while I put the caliper on.

6. The caliper went on straight in. Some gentle taps with a hammer helped get it all the way in. If it doesn't go in easy, take it out and try again.

7. Screw the cap screws back in.

8. Pump the brakes after each wheel is done to pre-load the calipers and pads and take the slack out of the system. I also like to stand on the brakes with the engine running (for full boost) at this point to check for weak spots in the line or hoses. It's better to have them go in the garage than out on the road.

9. Take the lug nuts off the rotor.

10. Put the tire back on.

11. Take the truck out for a mile or so and test it before you start on the other side.

The first set of pads took about an hour. The second set took about 1/2 hour, once I learned how.

The tools I used were:

A 3 ton jack.

A 3 ton jack stand under the front cross member.

A cross wrench (7/8") for the lug nuts.

A 3/8" Allen head socket. (A 3/8" Allen Wrench would have worked too.)

A carpenter's hammer with a claw.

A large flat blade screwdriver.

An 8" C clamp. (6" would have worked)

A trouble light.

Hope this saves someone some frustration....

Answer 3

you need to remove the cotter pin from the spindle,then take the nut and washer off. then it should slide off.

Answer 4

STEP ONE: Comfort first. Park the car in a cool, shady spot.

STEP TWO: Now safety. Block the rear wheels so the car won't roll once you jack it up. Put the car in park and set the parking brake firmly.

STEP THREE: Lay out your tools. Grab a tire iron and go to the front wheels. The tire iron is that long metal rod with a socket on the end of it that usually comes with the vehicle. You can also buy a really cool one (called a spinner) that looks like a metal cross -- in fact, it is a metal cross -- with different-sized sockets on each end.

What we want to do here, before jacking the car up off the ground, is loosen the lug nuts on the wheels just enough to break them free. So go do that. Work them off just enough until they loosen their resistance and become easy to turn with the tire iron. Now slip the jack under the car.

There are several places to safely jack up the car. If you have a floorjack, you can roll it all the way under to the center of the engine and jack it up using the K-member that holds the engine. Be careful not to use the oil pan, as you might damage it. If you have a smaller, single floor jack, you'll have to do one side at a time. Look for flat spots on the frame, immediately to the rear of the front wheels, or on the end of each axle.

CAUTION: Always use jack stands. Never attempt to work on an elevated vehicle held in place only by a hydraulic jack.

Okay, raise the front axle off the ground. Put your jack stands under each end of the axle, and lower the car onto the stands. A jack stand (see illustration) is a metal tripod with variable height adjustments. You should own two.

STEP FOUR: Remove the lug nuts and the wheel (the tire will be attached). Best to work on one wheel at a time, leaving the other side intact as a point of reference. As a safety precaution, roll the wheel/tire assembly under the front-center of the car, between the jack stands, and plop it down beneath the engine's K-member. In the event of a faulty jack stand, this will break the vehicle's fall and could possibly save your life.

STEP FIVE: Okay, take a breather. Now let's look at what we have before us.

A disc brake assembly is composed of the following elements: a caliper, two brake pads, a rotor, and some bolts and clips to hold it alltogether. It's a very simple design. Here's how it works.

The caliper comes in two flavors -- floating or fixed. Each works on a similar principle. The caliper's job is to squeeze the brake pads toward a centrally located metal plate -- the rotor -- producing friction, which in turn slows the car. Think of a hand slowly clamping down on a spinning record (or a CD, for you youngin's who've never heard the term "record" before).

The brake pads hover on either side of the metal plate. They attach to the inside of the caliper, depending on your car's design, with clips or bolts. They are composed of heat-resistant material that rubs against the rotor. When the brakes are applied, the pads move toward one another, gripping the rotor between them and slowing the wheels.

The rotor is that shiny metal disc staring you in the face right now. You can almost see your reflection, right? Get your eyes level with it. If you can't see your face, or at least its general outline, it may mean that the disc needs servicing or replacement. Below, we'll show you how to check this disc for scoring or marring, and what to do about that.

STEP SIX: Back to work. Remove the bolts holding the caliper in place. Gently slide it out and away from the rotor. Inspect the inside of the caliper. See the pads? They will be held in place by a bolt or a series of clips, sometimes both. Remove the bolts or clips holding the pads in place (remember, you left the other side intact to use as a reference) and work them free. Examine the pads. Is there any "meat" left on them, or are they worn down to the screws? If they're completely worn, you should've been hearing a metallic scrape for a while every time you applied the brakes.

Lay the pads aside and inspect the rotor. Can you see yourself in it? If the pads were worn into the metal, your rotor will be scored; you'll have trouble seeing yourself. Run your fingernails along the surface of the rotor -- careful, though; if it's been less than 20 minutes since you last drove the vehicle, they might still be hot -- first the side facing you, then the side facing away. Is it scored? Deeply? This next point is very important. If the rotor has any grooves at all in it, remove it at once. Now you have a decision to make.

If you have a scored rotor, you must decide whether to have it "turned" or to replace it. If you're short on money, take it to a local mechanic and ask him to "turn" it for you. What they do is put it on a special metal-cutting lathe and shave off several thousandths of an inch of metal until the disc is shiny again. Remember, though, one of the real advantages of disc brakes over drum is their heat-handling capability. By removing metal, you reduce the system's thermal transfer capacity. We recommend turning the discs only when you are short on bucks. The better way is to take the disc to the auto parts store, match it up with a replacement, and buy a new one. Last time we did this, it only cost us twenty bucks for a new rotor, a cheap investment in safety. You have to go there anyway to buy the new brake pads, as well as a few other things, so why not make it one trip. In fact, here's your shopping list:


new rotor, or rotors, if needed
new brake pads (bring the old ones, to match them)
brake pad grease (comes in little packets; they're cheap, so buy two)
STEP SEVEN: Go home and have a lemonade.

STEP EIGHT: Before you go any further, you must move the piston back to its "full open" position. The piston? you ask. Ah, we didn't tell you about that one, did we? Remember the hand-and-record analogy. As the fingers push down (equivalent to the brake pads wearing) the distance between the brake pads shortens. Now that we have brand new pads, we must return the system -- the hand -- to its original "open" position, to accommodate the new pads. There are several ways to do this.

First, find the piston. It is located along the back (closest to the engine) portion of the caliper. It's usually about three to four inches across, and resembles a small metal promontory with a flat top. See it? Depending on its condition and age, there are several things you can do to move it back (toward the center of the car). If it's new, try pushing it in with the heel of your hand. Doesn't work? Okay, then try a channel lock or a vise grip. Still won't budge? Then here's a suggestion. A neighbor of ours turned us on to this once, and it works great. Get a large C-clamp, place a thin piece of wood or cardboard over the face of the piston to protect the surface from marring, and work it back that way. As you turn the handle on the clamp, it will increase pressure on the piston, until it becomes flush with the surrounding metal. Then loosen and remove the C-clamp.

STEP NINE:Install the new rotor, if necessary. Remove the old brake pads from the caliper (usually held in place by several clips), but, before putting on the new ones, you must do something. Remember the little packets of grease you bought? These are used to lubricate the brake pads. Careful now -- not on the front of the pad, which comes in contact with the rotor, but on the back. The pads attach to the caliper via a plate-and-clip arrangement. The lubricant goes between the plate and the back of the brake pad. Got it?

Don't overlook this. If you don't do it, you'll get a horrible screeching sound every time you apply the brakes, like a dinosaur in heat (and you know how horny those velociraptors used to get). After you apply the grease, attach the pad to the plate and slide the whole thing into place.

STEP TEN:. Basically, at this point, just reassemble the system in reverse order of the way you took it apart. Now do the other side. Take the car for a test spin. Sometimes, with new brakes, you can get some weird scraping and scratching sounds; these will usually go away in a few days. Clean up, and you're done.

Don't underestimate the importance of a brake reline. As we said at the outset, absolutely nothing is more important than your car's ability to stop itself. Knowing more about your car's braking system -- getting in there and actually seeing what's going on -- empowers and informs you in a way that going to the corner mechanic doesn't.