Do costs in a US shop to machine an existing rotor vs costs in a Chinese or Indian shop to cast and machine a rotor from scratch and ship it to the US come out fairly similar? It's an interesting study.
Do dealers/shops actually still cut rotors?
- Thread starter Sequoiasoon
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Did you take into account the cast iron rotor structure, time under heat and the force excreted by the braking force?
Just dropped by track day forums for several popular cars, it appears that even though they get their rotors incredibly hot most of the "warping" is just residue of the pads on rotor built up unevenly.
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Science has done that for us. Read the first article I linked. The temps simply can't get there...unless you're driving a Formula 1 car. I guess I could concede a super-cheap Chinese rotor with a crummy and porous casting could conceivably fail, but it's still not very likely.
Yep, almost a certainty.
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Man in 2007 it was replace pads rotors together, always. Even under free maintenance. They’ve become so mainstream and get the money oriented
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Exactly. Think about Japanese cars where routinely a fair about of rotor surface is not swept by the pads. The rotor then rusts and there’s a large band or orange stripe that protrudes more and more over time.
German cars routinely have pads that sweep almost the entire surface, edge to edge.
The rust thst forms illustrates something that builds up on the rotor face and can’t be removed by pads. It happens too on the swept surface. There can be grooves, deposits, etc.
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Rotor is measured for thickness before they are turned.
And O'Reillys will cut them.
Don't all steel rotors develop surface rust if they get wet? Mine get surface rust after I wash my car. It's gone as soon as you drive the car and use the brakes.
The OReilly in my town still turns rotors/drums as far as I know. Personally I haven't bothered trying to have a rotor turned in a very long time as they are usually so rusted and worn that there isn't much left of them to turn when brakes are needed. Just replace the rotor and anything else that is needed during the job. The amount of salt they put on the roads here in Central IL is ridiculous.
If you need to swap pads and you have good coated rotrors that have been dynamically balanced it may be worth it to cut.
I know semi metallic pads like to chew up rotors but stuff like EBC yellow is actually pretty gentle and you can turn the rotor.
I know semi metallic pads like to chew up rotors but stuff like EBC yellow is actually pretty gentle and you can turn the rotor.
Do you do them on the vehicle or off on a lathe? What does your shop charge for pads/resurface?
I passed by AZ on way home and got new Duralast Elite to swap fronts. Old ones go back tomorrow. Worn but not crazy and at least I know my son will have new pads all around. Took it out, did the bedding, nice, smooth, quiet after that initial crazy transfer material grind. First time that happened I was like *** but after a couple replacements I expect it and they work good.
I had also ordered a new sway bar end link from RA. I replaced one last year but the AZ penalty was $40 vs $10 so only did one. Life got in the way and hadn't ordered yet. Well when I swapped front pads today, good thing I ordered that end link already and it will be here Friday.
Even back in the 90’s when I turned wrenches at a GM dealer factory rotors were very expensive. We turned drums and rotors daily. As time went on the cost of rotors dropped dramatically and so did the quality. Rotors now rust from the inside out and giant rust flakes break off from within. Cheap metal was to blame and the rust belt. I’m sure if you can find high quality rotors today they could be turned. I just bought AC Delco gold coated rotors for $54 each and expect they will last one brake job.
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It’s $189.99 including labor just got to buy the pads separately which are usually ~$70ish
Because they don't last very long after they have been turned and seem to warp easily. The cheap Chinese junk you are talking about seem to work good. I bought some new rotors for my Civic a long time ago and they are still working great.
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Oh and to add we only have a standard old school brake lathe. No on car stuff. I have used the on car ones before in school and I’ve noticed they never cut as smooth and you usually can’t cut just one pass on them.
Not saying it always happens, but it can. Get some foreign material between the rotor and the wheel bearing flange and hit it hard with an impact. It will warp and it can be verified with a dial indicator. I've seen it.
I also had one instance 20 years ago where a front wheel bearing had sudden failure on my Aerostar and I limped it an indy shop for front wheel bearings and rotors replacement. A week later, my brake pedal was pulsating like crazy, again verified with a dial indicator. It turns out the "tech" had put the lug nuts on so tight, a 24" breaker bar with a pipe was needed to get the wheel off.
While most steering wheel shake or brake pedal pulsation is caused by friction material on the rotor, not always.
Buddy of mine keeps trying to convince me of this. Also tells me the run out is from the bearing which is why if you replace the rotor it vibrates again in 10K miles.
I am unsure what to believe. His logic has merit technically?
All of the dealers around here cut rotors whenever possible. Techs like getting paid and on car lathes do an excellent job if they are used properly.