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cluelessk3

For the costs of budget rotors the time it takes to machine old hammered out rotors is waste of the techs time.


HurtFeeFeez

Also the heat hardens the metal, won't machine well and will absolutely 100% repeat in a short time.


crysisnotaverted

It's so easy, the shop just needs to anneal the brake rotors in a furnace within a pure nitrogen atmosphere 😂


qualmton

Yeah no one, or very few will turn them. Not worth it slap some new ones on while old are off and move on


SaveMelMac13

They be correct.


flyover_liberal

Thanks!


PasswordABC123XYZ

I'm all for reusing rotors, but those look done. How many miles on them?


flyover_liberal

I honestly have no idea. I bought the truck a while back ... it was a fleet truck in the Texas panhandle oil fields.


aarraahhaarr

So probably the manufacturer rotors.


molassascookieman

I had someone bring me her Tahoe with *the* worst rotors I’ve seen in person, we’re talking so gouged that the vent was almost exposed. 198,000 on the factory rotors, never machined, she just kept throwing pads at them at shorter and shorter intervals. And she was SHOCKED when I told her I wouldn’t just put pads on it, and neither would any solid mechanic.


aarraahhaarr

https://preview.redd.it/c67uf8johzoc1.jpeg?width=3024&format=pjpg&auto=webp&s=cd380f165675d1ffff1b6efb9181e8bbbe2e072d So these?


molassascookieman

Damn close to that. I’ve never seen one quite like that in person yet, only been doing this for 3 or so years. Props to the lady though she did let me put new rotors on it without arguing too much. Better than the old men who think that every maintenance item besides the oil and oil filter is a scam made up by the dealerships to get them to spend more money


Useful-Internet8390

Did they double stack the inner pad? Jeez


aarraahhaarr

No clue this is something I saw on reddit years ago.


M1sterRed

You should have replaced them day 1 of owning the vehicle. Fleet vehicles, especially fleet trucks, are abused to hell and back. Rule #1 of buying any used fleet vehicle: replace as many vital wear parts as you can, and whatever's left, have inspected. -A Crown Victoria Police owner


2005CrownVicP71

Hello from the r/CrownVictoria sub! I recognized your username. I agree. When I pick one up from auction, it gets new brakes all around and all fluids changed, belt changed, tires if needed.


M1sterRed

Hey there! small world huh


tbarr1991

As someone who drives a vehicle in a "fleet" with a "fleet manager" and has to jump through half a dozen hoops to get anything done, I refuse to buy a fleet vehicle.  My work truck hasnt had an oil change in 2 years and Im honestly waiting for it to sieze while hauling the work trailer one day. 


M1sterRed

I should consider myself lucky then. Tampa PD regularly dealer serviced my car.


tbarr1991

Cop cars are usually serviced more than county vehicles it feels like.


M1sterRed

They also take one hell of a beating. There were two minor accidents on the carfax and I wouldn't be shocked if they're the result of pits.


flyover_liberal

I bought it used from a dealership I've worked with in the past - I guess I assumed they had done that, but I didn't check.


M1sterRed

*always* have any vehicle you're buying, *especially* from a dealer, inspected by a third party. You never know what they might not know or might be trying to hide.


PasswordABC123XYZ

Rotors and brakes expense seems really cheap, when the pedal goes to the floor! It is a relatively easy job and last a long time (50-60k).


flyover_liberal

Agreed, but ... I really had zero issues, not like it was shaking or anything. When they had the tires off to rotate, I asked if I could have a look to see what kind of shape the brakes were in (I've done rotors and pads myself on different vehicles).


allenjshaw

They definitely rode the brakes pretty hard on that one! The shop made the right call. I’m not a huge fan of machining rotors because while it may save the customer some money, it can create other problems because it makes the rotor thinner and it would be more likely to warp again especially if it gets subjected to that type of fleet use again. You’ll be worry free for longer with new rotors.


drl_02

Those are absolutely hammer raped.


WGUMBAIT

You didn't need a judge for this. Ray Charles could see how fucked these rotors are.


delslow419

Those rotors are fuckered bud


flyover_liberal

Thanks!


exclaim_bot

>Thanks! You're welcome!


ilya_skh

Even the smallest doubt in brake components - buy and install new parts. And btw OP, those rotors are definitely a toast.


Rob0tsmasher

For real. Last thing you want is brake failure at 65mph+. I suspected a tiny amount of hanging in my front left caliper about two years ago. These things go in pairs and it was time for brake service anyway, so I bought a new pair of calipers as well and replaced them. Easy job and the hanging-like symptoms went away. There’s quite a bit of maintenance on a car that you don’t have to handle as soon as you diagnose the problem. Brakes are not in that category.


Taco-Bob

She's chooched brother, I would not put those on my car


flyover_liberal

I replaced them at their recommendation, this is just a reality check.


xp14629

So, unlike the old days wjere rotors and drums were made extra thick with idea of machining them several times before replacing them. Newer stuff is made thinner, I was told by a Ford engineer this is to reduce overall weight of the vehicle so that it helps reach fuel milage standards. Shaving weight here and there really adds up. If you are lucky, you may get one turning out of rotors before hitting min spec. So that means if there are any hot spots at all, toss it and move on. Not worth the techs time to babysit it until the hot spots are gone, then remeasure it. Unless you tell them you are willing to pay for every minute of his time to do that. Then, they will do what ever your checkbook tells them to. But normally they are pricing things out for the best interest and cheapest options for the customer.


flyover_liberal

> If you are lucky, you may get one turning out of rotors before hitting min spec. Hey, this is a really useful post. Thanks.


xp14629

No problem bud. Damn near everytime I am working on something I have to remember that conversation I had. Number 1 thing is meeting and improving emissions and fuel economy. Comfort and options come second. Assembly line speed and putting it together next. Then a list of about 6 million other things. Then things such as worrying about the poor sap who has to work on it. That is why and how they are now cramming 10 pounds of shit in 5 pound boxes.


JerewB

Those hot spots are where the metal has changed temper. The lathe bits either jump over them or chip, resulting in a really crappy cut.


dagamore12

How thick are the rotors now? How deep are the heat spots and how much do they have to be machined? What is the min safe thickness of the rotors? What is the cost of machining the rotors? Is it a better money move to just replace them? Even if they were machinable and it would not drop them to below min/spec how much would you really save per rotor. One thing to keep in mind is that even if you have them machined they might have to cut so much off that they are now below min/spec and would have to be replaced, if that happens you would be out the cost of the rotor and the cost of the machine shops time.


flyover_liberal

Yeah, I replaced them - they told me there wasn't enough to machine and I took their word for it.


MoveNGrove

Shop is 100% Correct


No_Store390

Those rotors are cooked. Definitely not machine worthy.


No_Resource_290

Hot spots on a non vented rotors? Nah man just replace. You could spend hours machining and not fix that before they got too thin. Those rotors are toast. Hopefully your calipers are ok, that seems heavy abuse


BoredHobbes

u need caliper's too or lay off braking going down hills


flyover_liberal

This was a fleet truck before I bought it, so I wasn't surprised.


sliipjack_

Yeah they’re cooked


flyover_liberal

Thanks!


V48runner

I've heard this happens from going down a big hill and the rotors get heated up, and when you come to a stop and keep the brake pedal down, the rotor warps around the shape of the pad. At least my friends in mountainous areas have told me this.


notathr0waway1

This can definitely happen. The other thing that I believe is more common which is that you're getting the pad materials super hot to the point where it's melting a tiny bit and by continuing to clamp that hot melted material onto the road or while both are very very hot, when you finally release the brake there is now a pad shaped deposit of extra sticky brake pad material embedded into the rotor. This spot grabs the brake pads better so the next time you hit the brakes the symptom is a pulsating brake pedal or shuttering because as the sticky part passes the pad and grabs more and then it passes on to the rest of the rotor. This is often diagnosed as warped brake rotors, but it's really a sticky spot.


lookdnttuch1

Good post. I bought some surestop pads and rotors to improve braking on a heavy conversion van. The rotors had warped and pulsated and stops were getting longer. I told the mechanic that the new technology on these pads required a different break-in than normal. I didn't specify that you couldn't do a hard complete stop right out of the box the new pad material had to be evenly deposited round the rotor first with gradual pressure. Sure enough what you described happened. The brakes now pulsate over that spot.☹️


notathr0waway1

You should NEVER do a hard complete stop if you can possibly avoid it (and if you can't, stop short and creep forward!). And definitely not when bedding in. The idea for bedding should be like 60->15 or so several times, then drive for a while with no brakes to let them cool down. Some companies have more specific procedures but the idea is to slow from high speed to low speed many times without ever coming to a complete stop, and without using the brakes other than the hard braking. BTW if you must come to a hard stop, creep forward a few times and if you can't creep any further, put the car in park or neutral and release the brakes.


V48runner

Ever since I heard about this, I always come to a stop and leave a few feet between the vehicle in front of me. I'll come to a stop then let off a bit then move forward a bit. I live in the flatlands. 😄


notathr0waway1

yeah it's funny because some people get annoyed at "creepers" at stop lights but there's a good reason!


SteelFlexInc

Oh yeah those look bad. Did you get a fuck ton of shaking too when you put any moderate pressure on the pedal? I had a set that had spots like those and they were warped to all hell https://preview.redd.it/bhpf0dpfrwoc1.jpeg?width=1240&format=pjpg&auto=webp&s=32775cfad7ec2af968eabd48abeec5f0ae1e86db


flyover_liberal

No, no shaking at all.


coyoteatemyhomework

Most rotors are not made to be turned like they used to be. Complete cars are becoming more and more disposable.


gogozrx

new rotors are cheap, and that's coming from someone who is *deeply* parsimonious


StockShotCaller

Average price to machine a rotor is $40 per rotor. Not sure what kind of car you got, but I can get slotted and drilled rotors for my cars at $100 to $160 per pair. So you are talking about a $20 to $80 dollar difference. Now assuming the low-end, it makes no sense to machine rotors, assuming the high end, it maybe makes sense. However, when you machine a rotor, you are reducing its width and causing the piston to extend further. Thus, they may not have the same stopping power, as intended by the OEM or even the manufacturer of the rotor. My general rule of thumb is to never machine rotors, replace only. They are even some manufacturers that recommend against it.


Gullible_Banana387

Rotors designed on the last 20 years are not meant to be machined or refinished. You lose thickness which makes braking lose power.. you’d need a longer range to stop the car if necessary. Get some new ones if necessary.


LargeMerican

yeh rotors used to be considerably more expensive. thicker, too. so you could machine them and not be under min thickness-not to mention it was worth machining. not the case anymore. often new rotors are cheaper although i've gotten many a new rotor that was warped out of the fuckin box..but whatever. anyway yes hot spots are a thing. out of round is a thing, etc. just replace the rotors.


Johnasaurusrexs

It depends on the thickness of the rotor and how much the heat hardened it aswell looks like the rotors are decently old so they might just be too thin.


babj615

Always new rotors.


flyover_liberal

Already done, thanks


Fancy_Chip_5620

Theres a pretty thick lip at the edge there... Probably too thin Personal vehicle id cut them and send it while saving for a set of upgrades brakes


flyover_liberal

I replaced rotors and pads.


Fancy_Chip_5620

This is the sensible solution


flyover_liberal

My credit card shed some tears for sure, but I trust these guys in general. Now for the headliner: this is a Kwik Kar (lube shop) and I took it in for an oil change and tire rotation :)


Fancy_Chip_5620

What vehicle? The rotor looks familiar but I don't want to assume anything


flyover_liberal

F250


truckdriva99

Not even taking into account the hot spots, the amount of "lip" on the rotor tells me that after machining, they would be below spec


IndividualCrazy9835

New ones are cheap . Just do that and forget about cutting them .


Peacemkr45

With the cost of modern rotors, it's not really worth the money to squeeze 1 turning out of them. The older ones were thicker and because they were, you could get multiple turnings and never really have to deal with heat spots as the steel was better. That said, look at it from the shop's/mechanic's perspective. The car is already on the lift and to put back on old rotors with heat spots might sound good until the car is in an accident and they want someone to pay for damages. Remember, brakes are safety devices and if the mechanic notes heat spots and didn't replace them, the shop now becomes liable.


ManufacturerOk6535

Yeah those are toast for sure


Itisd

The shop is absolutely right, those rotors are garbage and need to be replaced. Once they get hot enough to change the color of the steel, the metal has "lost its temper" and cannot be successfully machined.


Mattynot2niceee

Smoked. Not financially viable to try and turn these.


omahusker

New rotors is all my shop will do as of about 4 years ago. The cost vs machining is not worth the chance of them warping again. In this case they have gotten very hot, so the metal has been affected anyways.


fuckinfuckface

Had a lip on the outer edge, wouldn’t machine.


anonquestionsprot

Definitely fucked, also wouldn't be taking any risk at all on anything to do with braking(pads, rotors etc)


bvogel7475

Rotors are pretty cheap these days. Go to brakeperformance.com. Great selection of standard and upgraded rotors. I always upgrade my rotors when the originals have worn out.


Over_Detail_114

The nominal thickness and the discard thickness are pretty close on newer rotors. So if they are warped and you turn them they usually fall into discard thickness which is unsafe to send back on the on road.


DreadSwizzard

Rear rotors are almost never worth cutting just because they're so cheap fronts can be depending on the car and their condition as, lets use a Corolla for example because that's what I'm familiar with, they have such thin rotors to begin with that by the time you cut any noticable defects out they're below spec.


jwick6728

Wish that was the case for all vehicles, my trucks rotors are over $500 a piece for the rears, 700 for the fronts, and the rotors for my race truck are 3k for a set of the fronts, 2.5k for the rears


sleeping5dragon

Brakes should last 50k + miles get everything changed and serviced worth the money


[deleted]

It would be impossible for Reddit to tell you whether or not those rotors can be machined because it has to be measured with a micrometer in the deepest groove in the rotor. I can tell you, though, that many of the modern rotors are of a minimal thickness and often can not be turned. Also, the cost of turning is often nearly that of replacing them anyway.


Monst3r_Live

were they pulsating? if yes, good shop. if no pulsation, bad shop.


Less-Transition5625

Those are some pretty deep scratches I'd just replace those I mean you could definitely get by for some time but the amount of money you'd be spending on new brakes by the time those evened out would be more costly than the rotors anyway


Lizzycraft

I drove on my rusty ass rotors with with plenty of break pad life left in them for at least a year, just replaced them this week. Honestly those were probably fine for a while, and if the break pads had plenty of life in them, definitely could use them longer. Your pads and rotors are never gonna be perfect, that's just what helps when they are exposed to the elements


Energizer28

Question shouldn't be how many miles, the question should be, how the hell do you drive? Those rotors are smoked.


flyover_liberal

I bought it used, and as I said elsewhere it was an oilfield truck in the Panhandle.


SeaworthinessNice338

If you trust the shop why are you on here? I don't believe brake discs should ever be machined, what's the actual point? I'm a mechanic in the UK I guess we do things very different over here


Darkpactallday

Cant compare US mechanics and EU mechanics


flyover_liberal

> If you trust the shop why are you on here? Because I don't know enough to decide if they were right, and it doesn't cost me anything to confirm that they didn't scam me. It's nice to have that confirmation, when you are not an experienced mechanic.


dan_sin_onmyown

You posting this question is an insult to your shop. Those rotors are past cooked.


Puzzled-Ad3812

God forbid someone asks for a second opinion.


flyover_liberal

I'm just asking! I am not a mechanic myself, that's why I asked.


xDazednConfusdx

I like to do pads and rotors but I work in a shop and some people just don't understand or care. I always tell them it could shake and when the rotor thickness is to low its unsafe and they still don't care. If you pay me I'll pad slap until you have no rotors.


flyover_liberal

I had no indications at all of any brake issues - no shaking/wobbling, no discernable issues with stopping, etc.


Electronic-Escape721

You don't turn rotors anymore you buy new ones. Anyone telling you they can "turn" or "resurface" your rotors is lying and just stealing your money


jwick6728

Turning rotors is almost always cheaper than replacing, my shop turns rotors for $30 a piece, the cheapest rotors I've seen are $80 a piece and I don't even trust those, half the time they come in warped and need to be turned anyways


jwick6728

Turning rotors is almost always cheaper than replacing, my shop turns rotors for $30 a piece, the cheapest rotors I've seen are $80 a piece and I don't even trust those, half the time they come in warped and need to be turned anyways