Took my 08 328i to the dealer for a rotor change. You only need to measure to the nearest 0. On the other hand, if the rotors still have plenty of metal and show no evidence of hard spots, cracking, severe grooving or rusting, and there are no complaints about pedal pulsations, the rotors can be resurfaced as needed to restore a flat, smooth friction surface. Hi,It is a brake rotor, and is the physical disc of a disc brake. Most procedures often say you can simply use a micrometer to measure rotor thickness, in 8-10 different places.
Why not just wait until the light comes on. At the same time, moisture is building up in the fluid. If not, the car needs to be serviced immediately. If its close to min spec its garbage. Is 1mm thicker not good enough for a change?? Mostly the thickness is used to sell you rotors. They are telling me that my rear rotors are currently at 19.
But your dealer told you to change at 4mm. Interesting, your Tampa dealership said at 4mm pads needed to be changed. Many people said measuring rotor thickness is an important aspect of doing a brake repair. But this increases pad wear and decreases overall pad life. The finished measurements could even be printed out from this handheld unit. The system measures both thickness and lateral runout, and generates a hard copy printout of all data.
I have read that I should measure the thickness in several different places. Wear is checked by measuring diameter with a drum micrometer. So, I agreed to get the pads changed. When a hot rotor cools quickly, like when sitting in a deep puddle too long, the rotor may not return to this original form and begin to distort or warp. I guess what I am asking here is.
I've got about 130k on my rotors and still within spec, stops nice and straight. All rotors on the vehicle usually undergo the same amount of wear. How disc thickness variation occurs? You can use small spacers to get around the lips spacers at the pointed ends of the caliper between the jaws and the surface of the rotor , then deduct the thickness of the spacers. Importantly, all the readings should be above the minimum requirement for thickness. After several years of service, the fluid may contain as much as 3% water -- which is enough to produce visible corrosion in the caliper bores and on steel pistons.
If your brakes are operating smoothly, the values won't change much at different locations. Or you could sand down a piece of scrap aluminum from an old pot picked up at a thrift store. Rotor thickness is one thing, but you also need to think about heat cycles. The heat is absorbed by the disc portion of the rotor, and is dissipated by the cooling fins slotted vents between the faces of the disc. Doing this will make sure that the rotors have enough metal left for safe braking. To ensure that brake rotors can perform properly without problems such as runout or warping, vehicle manufacturers perform dynamic testing. But as a seal ages and loses elasticity, it doesn't do as good a job of pulling back the piston.
You should never turn a drum that's worn more than 0. It will also reduce the thickness of the rotors, shortening their useful service life. Thickness must be checked with a micrometer at six or more points around the rotor. Is the dealer going to remove the rotors, put them on a lathe and resurface them? As a rotor wears and becomes thinner, it has less mass. My rear back pads had 4mm and the rear rotors were 1mm above spec, which sounds a lot like your situation. Most carmakers insist rotor quality is extremely important.
This must be measured with a dial indicator against the face of the rotor. The Discus could measure rotor thickness and lateral run-out and compare it to vehicle specifications which were stored in the on-board database. Took my 08 328i to the dealer for a rotor change. However it may be, 2 mm is a common rule for safety reason. These boys and girls have special training that allows them to evaluate the state of your brakes. Nowadays, in order to reduce weight and save some costs, many automakers often produce rotors with thinner thickness. Rotor thickness is one thing, but you also need to think about heat cycles.