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38

The decision to replace is largely based on the thickness. The repair manual should tell you the minimum thickness, below which you should replace the rotors when doing the repair. Use a pair of calipers and measure the rotor thickness, if you're below this number you need to replace the rotors. You may also wish to replace the rotors if you have ...


19

Cars falling off jackstands are no fun. If you're careful you can heat up the rotor with a torch prior to whacking it with a heavy mallet. If you're not careful, you run the risk of warping the rotor (which is ok if you're getting a new one). Don't try this near fuel lines or the gas tank.


13

There are three cases that cause brake rotors to need to be resurfaced/turned and/or replaced. Gouging of the rotor by the brake pad holding mechanism (the pad were rubbed completely away and the metal holding the pad start digging into the rotor) Warping of the rotor from extreme use (rotor gets too hot and warps upon cooling) The rotor itself wears down ...


13

Drum brakes are cheaper to manufacture than disc brakes, because there are fewer moving parts and because in the rear the parking brake (which often works by a drum-and-shoe mechanism even on four-wheel-disc-equipped cars) can share a drum with the "regular" brakes. All other things being equal, discs work better than drums, especially in wet conditions. ...


13

I would recommend you get slotted, but not drilled rotors. Regular rotors will work fine for typical track use. What is more important is the type of brake pad you purchase to go with your disks. The reason I suggest not getting drilled rotors is, they have a tendency to crack at the holes due to stress risers. They will not last as long as you'd like them ...


11

The braking surfaces of a rotor require precision machining. The tolerances are in the .002" range. You would never come close without a quality lathe. Each manufacturer also has specifications for minimum total thickness, side to side variance for vented rotors, the smoothness of the finish and run-out which is the difference between the highest and lowest ...


10

Wow, I'm in the minority here. It is my firm belief that you should have your rotors turned with every brake pad/shoe replacement! If you do not do this everything will work perfectly fine, until you apply the brakes then if your brake rotors/drums were glazed, heavily scored or worn out of parallel to the new brake pad your will stopping distance WILL be ...


10

The only way to know if a rotor needs to be replaced is measuring it with a micrometer and comparing that to the manufacturers specifications, so, no, we can't tell you if it needed to be replaced. However, since this was your first brake job I seriously doubt they needed to be replaced. Common practices is to "turn" rotors when doing a brake job. The ...


9

You're going to have to bed the brakes in properly. Be very careful. http://www.zeckhausen.com/bedding_in_brakes.htm follow these instructions (at your own risk). A friend had a similar car as yours (IS300) and had the same problem. Once I bedded the rotors in, noise was minimized.


9

No, it does not need to be done every time. Don't believe the hype. If you have warping, then you should re-surface, provided you have not worn beyond the minimum dimensions for your discs.


9

Improper wheel nut torque, use a torque wrench, or an impact wrench with torque sticks to put on the wheels. Rapid cooling such as running through water with the brakes hot is also suppose to cause it. Cheap pads, they breakdown under heat and leave deposits on the rotor surface. Ball joints should not cause the rotors to warp. Example of Torque sticks ...


9

Contact area Blank rotors have a larger area in contact with the pads than slotted or drilled rotors. Therefore they provide better braking at the same temperature. Cooling To cool the rotor, manufacturers use a vented rotor, not a cross-drilled or slotted rotor. cross-drilling puts holes perpendicular to the flow of air - they have no cooling effect ...


8

In a word, accuracy! A lathe as used by a mechanic will have the precision required, and the instrumentation available, to ensure the rotors are turned evenly. You'd be surprised at how much vibration you can get at 70mph from the smallest inconsistencies in rotor height - and how much you lose in stopping power!


8

If your guide pins are stuck, the caliper won't be able to slide properly. With a sliding caliper, when you apply the brake, the piston pushes one pad against the disc (rotor), and simultaneously pushes back against the caliper (Newton's equal and opposite reactions), causing the caliper to slide along the guide pins, and pull the other pad against the ...


7

It's probably that the pads need bedding in as NoCarrier says. However, my sister-in-law once had her brakes start squealing even though there was plenty of pad left, and the problem ended up being a small stone that got stuck between the pad backing plate and the rotor, in front of the edge of the pad.


7

Assuming there is not a screw holding it on (your experience with the other side tells you this), just give it a solid smack with a hammer. When I worked for Mercedes, it was not uncommon to need a 2-lb sledge to knock the disc loose. We would use two hands and swing really hard sometimes.. never heard of a messed up bearing from that. Of course, this ...


7

You cannot tell from just looking at them (in most cases) ... you have to measure the thickness of the rotor to see if they need replaced. Also, it's hard to tell from the picture how deep the wear is on the rotor. The grooves could be 1mm deep, or 5mm deep ... it's really hard to tell. It really comes down to how thick the rotors would be after machining. ...


6

In my experience when removing the old type of brake hubs you would need to hit quite hard without that hurting the bearings. You might try spraying the disc with WD-40 and let that soak in for a bit and then knocking it again with a hammer. You would wan't to spray mostly around the bolts that fasten the wheel since there is most likely some corosion there ...


6

If your rotors are thick enough and there are no defects in pads area (big grooves, buldgy edges) I would not worry at all. There's no need to replace rotors each time. If there are some defects that can be removed and the rotors are thick enough - consider resurfacing the rotors, that might be cheaper. All-in-all, given that the only downside is faster ...


6

Paulster2 offers sound advice when he says the pads need to be replaced sooner rather than later. I recently took a picture when I performed a brake pad swap that offers a stark comparison of what you could be missing out on. The new pads for my BMW measured 10mm at the thickest part. The old pads were roughly 2mm, thin enough to cause my brake pad wear ...


6

I've done countless brake jobs at the shop I worked at; without hearing/seeing the car here are some things that can cause noise/pulsating: Non-burnished brakes - like others have stated after putting fresh pads and rotors on a car you need to 'break them in.' I worked in a shop for a while and we didn't always do everything by the book, but when putting ...


6

It is not normal for the front end to go out of alignment when getting the front rotors turned, but it would not be unheard of. Any time you mess with the front end of the vehicle you run the risk of needing an alignment. This is not something you should expect to be done, though. Something which may be happening is you may have a caliper which is ...


6

I was looking at this from an automobile standpoint wondering What the heck is he talking about?? The vast majority of vehicle rotors and drums are made out of grey cast iron!, then went back and reaslized you are asking about motorcycles and ATVs. To that end: Why are OEM parts made of martensitic stainless steel (AISI 4XXX series)? The main reason ...


5

What you're describing sounds unusual. In an ideal situation, when you brake, even if you lock up the tires, you're going to continue moving in the same direction unless some outside force acts upon the car. To spin a car 180 degrees requires a mechanical malfunction, or an outside force. Start with the tires: are they the same on all 4 corners, and ...


5

The main reason for reoccurring warping seems to be (form what I've read) "imprinting" your pads on the rotors: fully applying the brake on a very hot rotor for an extended period of time (a few seconds), thus leaving behind a deposit film that causes the warping problems. Maybe your pad is dragging on the forward rotor, causing it to heat up? With the way ...


5

2mm of friction material is not much. I would suggest you change the pads as they have. They may last a bit longer, but at what point are they going to go metal-on-metal and greatly reduce your stopping ability? At any point, the last little bit may flake off and cause this situation. It could run for 5000 miles or it could last 5 miles? Are you willing to ...


5

I found what was causing the noise. There is a small metal plate, roughly sized and shaped like a one of those little wooden ice cream spoons that come with a Dixie cup. It is positioned suspending from the bottom of the hub parallel to the back of the rotor. On both sides of the car it was touching the rotor causing the noise. On the driver side the ...


5

More than likely you didn't bed your brakes correctly. If you read this from Centric Parts, you find out exactly what I'm talking about. The specific part I'm talking about is the portion on an even transfer layer: Note the emphasis on the word even, as uneven pad deposits on the rotor face are the number one, and almost exclusive cause of brake judder ...


5

Grey cast iron possesses some traits which makes it less desirable than martensitic steel for brake disc applications: it is more brittle, which means it is easier to crack it has very low impact resistance, making it less durable under heavy braking it has less hardness (400 Brinell vs 700 Brinell), so it wears more quickly if left uncoated, it is more ...


4

I don't know about your model but most discs I've encountered have a couple of threaded holes in the hub part. They are often clogged with general road crud, so you may need to scrub the disc hub down to find them. If yours have such holes get a couple of bolts to match and screw them in, as evenly as practical. This will push the disc off the axle.



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