Although it is recommended by Ford to replace all four wheel brakes at the same time for safety, your idea should be OK. Is it better to resurface or replace rotors?
Resurfacing Issues Resurfacing a rotor obviously removes metal, making the rotor thinner and reducing its remaining service life. Because of this, some consumers as well as some vehicle manufacturers say rotors should not be resurfaced every time the pads are replaced unless the rotors are badly grooved or uneven.
How much does it cost to get your rotors resurfaced? Know what price you should pay to get your vehicle fixed. Estimate does not include taxes and fees. Do you need to sand new rotors? If your rotors are in need of resurfacing, only a brake lathe will do the job.
Sanding by hand will not only take an extremely long time to remove enough material, but you may end up removing too much material or end up with an uneven rotor which will only further necessitate the use of a brake lathe. How many mm should brake rotors be? The standard solid rotor is 12mm 0. It should not be ground to less than The standard vented rotor is 20mm 0. How often do rotors need to be replaced? In answer to how often do brake rotors need to be replaced, they can last anywhere from 30, to 70, miles, and sometimes more.
A licensed mechanic can evaluate the rotors and advise you on their status. How often should you replace brake pads? In some states, this is the law. Replacing one worn-out rotor usually means replacing both rotors on the vehicle, since they usually experience the same amount of wear.
A significant difference in rotor thickness may cause the brakes to pull toward one side. Advertisement Uneven Rotor Wear Uneven wear is another problem that can ruin a rotor. As long as a rotor runs true and has minimal lateral sideways runout less than. But several things can cause a rotor to wear unevenly, resulting in thickness variations that produce an annoying pedal vibration when the brakes are applied.
Excessive runout in the rotor or hub can result from a stack up of manufacturing tolerances or poor quality control. Advertisement Rotor runout also can be corrected using a conventional bench lathe, but it requires a multi-step process. First, you have to measure and mark the point of maximum runout with the rotor on the vehicle. Then, you have to mount the rotor on the lathe arbor and attempt to duplicate the same amount of runout on the lathe. Then, you can cut the rotor true and remount it on the car in the same index position as before — and hopefully the runout will be gone.
Rotor distortion and runout also can be caused by overtightening or uneven tightening of the lug nuts. If somebody zips on the lug nuts with an impact wrench, the uneven loading of the lug nuts can twist and distort the hat section of the rotor, causing the disc part of the rotor to wobble as it rotates.
Using a torque wrench to give a final tightening to the lug nuts prevents this kind of distortion. Advertisement Dirt or rust between the rotor and hub also can create runout. Cleaning the face of the hub and the inside face of the rotor hat section with a drill-powered circular brush can eliminate this cause of runout.
Hard spots in a rotor casting also can cause uneven wear. The hard spots resist wear while the surrounding softer areas experience more wear. It only takes about. Shaving off the high spots may allow the rotor to run true for a while, but sooner or later uneven wear will cause the high spots to return.
The only cure is to replace the rotor. Advertisement Corrosion Corrosion also can kill rotors. All rotors rust to some extent when a vehicle is parked and is not driven for a period of time like a week or more, especially in a damp environment.
Some rotors are worse than others when it comes to rusting. To reduce costs, General Motors reportedly deleted chromium a rust-inhibiting ingredient that has been used in some of their cast iron rotor alloys. The result has been some severe rusting problems with GM original equipment rotors.
Rust is bad because it weakens rotors over time, and makes the brakes noisy when the vehicle is first driven after being parked. Rusty rotors also increase brake pad wear. The pads will usually scrape the rust off after a few stops, but until then the rust is interfering with the pads and reducing their stopping ability.
Heat Effects Heat management is another factor that affects both rotor wear and braking performance. When the brakes are applied, friction generated by the brake pads rubbing against the rotors creates a lot of heat. 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.
Vented rotors are almost always used for the front brakes, while vented or non-vented rotors may be used in the back where braking loads and heat are usually less.
The number, spacing and shape of the cooling fins also is important because some designs are more efficient than others. Replacing original equipment rotors with ones that do not cool as efficiently because of reduced fin count or fin design may cause the brakes to run hot and increase the risk of brake fade. Advertisement Aggressive driving, pulling a trailer, hauling heavy loads or mountain driving all can cause brake temperatures to soar.
Over time, this will increase both pad and rotor wear, requiring the brakes to be serviced sooner than would be necessary with more normal or light use highway driving. If you live on a dirt road especially one that is treated with calcium chloride or you live in an area of the country where salt on the roads is common in the snow or near the ocean, or both , the likelihood of corrosion developing on and eating up your rotors is higher. Heat While heat is essential to the braking process, excessive heat will cause your rotors to wear faster and unevenly.
And if you rotors are unable to deal with excessive amounts of heat, they will transfer it to other brake system components. Excessive heat can even cause the brake fluid to boil and add unwanted vapor to the system, causing your brakes to become less effective.
When you brake, friction builds up between the brake pads and rotors. The heat is absorbed by the rotor and dissipated by slotted vents, or cooling fins, between the faces of the disc. Some rotors have holes in them to vent the heat, whereas others have no vents at all.
Excessive heat can be caused by your driving style. If you ride your brakes or brake aggressively, not only will you wear your rotors faster, but you will also cause them to overheat. Pulling a trailer or hauling a heavy load is also harder on your brakes and causes more heat to develop, as does driving in stop-and-go traffic or through hill country. Overheating leads to hot spots and glazing, the former causing your pedal to pulsate, the latter making it difficult to stop quickly.
Inspecting Your Rotors Any time your brake pads are replaced, your rotors should be inspected for overall condition, minimum thickness, runout, and signs of glazing or cracking. An inspection will reveal whether your rotors are in need of resurfacing or replacement - or in some cases nothing at all. Some repair shops offer a courtesy inspection when you schedule an oil change service. Unfortunately, with the emergence of extended oil changes on late model vehicles, inspection of other systems may be delayed, including the brake system.
And things can go wrong with your brakes between oil changes. When you are having your brakes inspected or repaired, make sure to enlist a qualified technician at a trusted repair shop. A complete brake job should consist of more than simply slapping on a set of pads, but a lot of cheap brake services do exactly that.
Most likely, your brake rotors will require resurfacing or replacing roughly every other brake job. Resurfacing Your Rotors When a brake rotor wears unevenly, or grooves are worn into it, or corrosion develops on its surface, one remedy is to have it resurfaced.
Resurfacing is the process of machining away a small amount off of the faces of a rotor. This is done on a special machine and creates a new face that is smooth and spins true. For that reason, resurfacing is less common today than it once was. Late model vehicles often feature thinner, lighter rotors that simply do not have enough metal to machine, at least not very many times.
Some manufacturers do not recommend resurfacing at all. If a rotor has enough material present - and if the manufacturer recommends that it be done - the rotor can be resurfaced. Rotor Replacement If a rotor is worn down to the minimum thickness specification, or it cannot be resurfaced without doing so, or if the manufacturer says it needs to be replaced, then it must be replaced.
Fortunately, the cost of rotors has come down in recent years, making replacement a less painful process. In fact, replacing some rotors with aftermarket alternatives costs only a little more than resurfacing them. For cost-conscious drivers, this is a plus. Others might prefer to err on the side of safety and longevity and choose original equipment rotors or higher-end aftermarket ones.
Another advantage of new rotors is that they are essentially ready to install right out of the box.
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