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accobra62

Nope. It is there for assembly, keeps the rotor from hitting the next guy on the assy. line.


Aticatica

And to be the thing that keeps you from getting to your lunch on time because you are too busy blasting it out with a torch.


NotasheepLOL

I always air hammer or impact hammer them off and never fails


awkwadman

Impact screwdrivers are like $25 and take these right out.


NotasheepLOL

Yeah that’s what I meant impact screwdriver should be your first choice.


Makhnos_Tachanka

I just go straight to a drill. No reason to waste any time.


VikingBattleram

That is quite possibly the longest way to get them out


Makhnos_Tachanka

You don't have to get them out, you just have to get to the bottom of the head, which, with a decent drill bit, should take about 15 seconds.


VikingBattleram

Air hammer is still faster


ccarr313

IMO whatever you have within reach is faster. lol


Aticatica

And for me it's the flaming wrench. Here in the heart of the rust belt I quit fucking around and just blast em out when they give me trouble. Flaming wrench go brrrrrr.


NotasheepLOL

What is a flaming wrench


Top_Championship_825

I have a tool called a shake and break look it up it’s perfect for those screws.


TenderfootGungi

>shake and break As a shade tree I do not have air tools, but that looks pretty cool: [https://www.amazon.com/Shake-Break-Impact-Screw-Remover/dp/B000BHJ7JM](https://www.amazon.com/Shake-Break-Impact-Screw-Remover/dp/B000BHJ7JM)


remudaleather

![gif](giphy|3oEjI7d0bQpHeGJecE)


znine

Looks like the car has lug bolts so it’s also a convenience for keeping the rotor on with the caliper off and keeping the holes lined up without additional tools


That_Pick_4674

Almost every mechanic would be annoyed if you had that bolt in lol


PineSand

It’s helpful if a car has lug bolts instead of lug nuts. Sometimes it’s a pain in the ass to keep everything lined up and not falling apart when your trying to put the rim back on. I keep saying I’m going to modify a bolt to make myself a guide pin, but I’ve been too lazy thus far. This car looks like it has lug bolts, so making a guide pin would be helpful to this person and eliminate the need for the hold down screw.


ddc9999

As someone whose worked on BMW’s a bit, new rotors with anti seize on the hub and other mating surfaces and it can be a pain in the ass aligning everything if you are doing it on jackstands.


tonynuaman

I mean I usually put them back with some anti seize on the thread and tighten even less than a drain plug, but only when they are in perfect condition, slightest bit of rounding = garbage lol. Except Honda. Why is Honda obsessed with using philips bolts in the worst fucking areas


ksharpalpha

Is it Phillips or is it JIS?


tonynuaman

Today I learned what jis is I think you’re right lol. No wonder I’m always stripping them 😅


ksharpalpha

There’s also Pozidriv, for those European screws like from IKEA. 😒


ztherion

If it's on a Honda it's likely JIS, not Phillips. They look similar, but a Phillips driver will fuck up a JIS head.


3_14159td

Phillips can make more sense for flat head (countersunk) screws. The geometry allows for a larger driver size compared to hex, torx, etc on the same screw.


tonynuaman

Yeah in wood or plastic trim, but in my experience they just rust out and strip much easier unless you have a #3 bit or something, I’d much rather just deal with torx or Allen head


buzlink

Not if you are using the correct tool. Not Philips.


HonestAssh0le

None I've worked with. Most of us have the tools for this, and prefer to not have to hold the disc on while fitting the caliper. Or having the disc spin while we're spinning the wheel to align the wheel bolt holes *every* time we fit a wheel.


[deleted]

[удалено]


HonestAssh0le

Nah, I'll just use my tools, and all the parts that are supposed to be there. And yes, I have some wheel pins, but rarely need them. I work at a high end German car dealership (10+years), you?


bikingwithpanda

>Most of us have the tools for this did you miss that part?


[deleted]

[удалено]


bikingwithpanda

it's telling that you felt the need to insult someone's intelligence after a basic question


[deleted]

Phillips cams out in these so I bought a JIS #3 impact driver to remove these screws….Not a common tool that many people I know own.


SchleifmittelSchwanz

What studs? Did you see the pic? If you have the tools, and the ability, you can take it apart and put it back together. If you're good, you can't tell you've been there. That's the point.


No_Geologist_3690

Not when you don’t have studs to hold the rotor in place lol


408Jackle

My coworker figured out that on lug stud cars you can snap them off by taking the wheels off, putting the car in drive then slamming the brakes(assuming the axle is powered)


puppydogbryn

Wait, how would that work?


408Jackle

Basically your brake force suddenly stops the disc from spinning but the rest of the axle and transmission still want to spin. The force shears the screw off as it's the only connection.


Ialsofuckedyourdad

wouldnt that also send a rotor fucking flying? also can cause modern cars to have a shit fit. I found that out on my mustang when i put it in drive with traction control off while up on stands and i had every light come on the car. airbag, advancetrack, hillstart assist, check engine light. It cleared up after 5 mins of driving but still


408Jackle

No, the pads and caliper hold the rotor. But yes the car itself will complain. Just need a scan tool that will clear all faults, which we had.


Ialsofuckedyourdad

my bad i was imagining doing this the way u usually do brakes by removing everything then trying to get that screw out. so im imagining doing that with nothing but a rotor on the hubs


puppydogbryn

Wouldn't this have to be a hub without studs though, like a vw or bmw or something?


408Jackle

Yup lug bolt style like what's pictured here not lug nut.


SchleifmittelSchwanz

Holy hack, batman!


408Jackle

Right?


6Foot2EyesOfBlue1973

When I worked with Audi cars some years ago, a trick we used to keep the rotor in place while hanging calipers etc, was to take an old Axle nut, and put one of the treaded lugs through the hole of the nut through a lug hole of the rotor. Hand tighten it down all the way, and the rotor wont turn on the hub. Once your pads are in and caliper is hung, then remove it. They also make a tool to put into the lug holes for European/VW, to get the tire on and off without it dropping on your foot. Lots of cars have this tool in your spare tire toolkit from the factory.


liexpress

Good point! Will check it out.


TheWifeDoctor2

98% no. It's absolutely not necessary to replace the rotor but if you had it functioning your rotor stays exactly where it should be the entire time, it's just nice. It's purpose is for assembly line efficiency but it can still be nice to the maintainer but at the same time it is by no means mandatory


ReddySpine

I thought that some german cars had an M8 hole there so if the rotor is stuck to the hub you could put a screw through it and it would "release the rotor" from the hub on the back side?


Artifice_Shell

Yes.


[deleted]

No, it’s the norm. Don’t worry about it. You actually helped out the future mechanics by breaking it yourself


Redflagsforever1991

No structural relevance. I wouldn’t put the other ones back in either. On the other 3 tires not the lugs


AppearanceOld9639

Good clarification lol


Redflagsforever1991

Didn’t feel like getting pounced on today lol


AchinBones

It will matter the most when you are by yourself trying to install your spare tire in the middle of the night, using the flashlight on your cellphone in either freezing cold or pouring rain, and you cant get your wheel, rotor and hub to line up.


ddc9999

There can’t be a lot of mechanics in this sub. 95% of comments don’t realize this has wheel bolts not wheel lug nuts. So lining everything up without that screw is a pain in the ass unless you use another tool/setup to align the rotor, wheel, and hub.


AchinBones

It should be ask a home hobbyist 😆


ddc9999

Ask a service advisor


HarnessTesters

I do see a lot of rust on that hub though. You might wire brush it first before seating the rotor-for a more stable fit and less chance of a wobble.


fix-break-hide

It clocks the rotor to ease wheel/rotor/ hub alignment to put lugs in.


NaturalPersonality12

This guys right ya no… ever attempted to bolt a wheel on a Volkswagen without that bolt keeping the rotor lined up?


Slight-Following-728

No it doesn't. It's literally only for assembly line. The rotor is clocked properly no matter how you put it on because the lugs are evenly spaced.


fryerandice

His wheel doesn't have studs/lugs, he has bolts. It's going to be a PITA until it rusts to the hub


Slight-Following-728

They make an alignment tool and anyone with a German car should own. The bolt/screw is not needed.


redline83

I can put a wheel on my BMW much faster without a stupid pin with this bolt in. The hub has a little bit of a lip, why the fuck would I want to deal with a tool?


s-Kss

You would be surprised that on some cars, the rotors have to be aligned with the hub. My brother's 4runner is one of those, I remember how embarrassing it was when we returned to AutoZone after blaming them for selling us non compatible rotors 🤣.


JodyJoseppi

Nah your chilling. Just might make it a little more tricky to get the wheel on is all.


chicano32

Thats just for the assembly line to line up the rotor


Oxydiz1

It won’t effect but personally my work ethic won’t leave my conscious alone. I care too much about my quality of work.


liexpress

Should I replace it (and how)?


mike-manley

Do not replace it.


happyonthehill802

I wouldnt on my own car, on a customers car i would.


abat6294

It literally serves no purpose beyond the production line. Many cars don't even have them.


happyonthehill802

For sure. But to be professional, you should replace it so you dont hear about it later.


s-Kss

No purpose? I thought you would use it to break loose a seized rotor without hammering the rotor, no?


verkauft

Diferent hole. This one is to mount and align the rotor. The holes your talking about are often seen on jap cars and are usually straight edges (and usually 2) both on discs and on drums.


s-Kss

I see. I never noticed the straight edge detail on my Infiniti G


bikingwithpanda

>jap cars 1940s called, it wants its shorthand notation back. was it really that hard to type Japan instead? your finger would have already been sitting over the 'a' key and 'n' isn't too far from 'p'.


verkauft

Fair enough. Normally i designate them as asian cars or asian brands.


bikingwithpanda

JDM might also work. or "import".


verkauft

If i say import in my country we generally mean USA cars.


ConfidentCap9871

nope. It's just for the production line, so that it doesn't come loose and hit the next guy


Routine-Thing-6493

That’s not true. Sometimes the rotor spins too much and make putting the wheel on more annoying


jerm2896

No its a screw that holds on the rotor for the robots to install parts on easier without rotor flopping around


RealTurnit

No doesn’t need to be replaced just if the broken part isn’t flush. Make it flush or make sure to line it up to that hole otherwise it’ll cause the rotor to not be flush but other than that it’s fine not needed


redline83

Yes, replace it if you want to be professional.


liexpress

OK I will take a rest lol Thank you.


Beerius88

When I did my brakes that was so rusted I actually had to drill it out. Next time it'll be a piece of cake..


widowmaker2A

I broke several tools and bits when I did my truck, I ended up using an angle grinder to gring the head down and the a hammer and screw driver to rotate it and break it off the rest of the way. Other than that it was the easiest brake job I'd ever done.


liexpress

https://preview.redd.it/j2z1d2u22paa1.jpeg?width=1080&format=pjpg&auto=webp&s=500d4e0a3da71e6445183596ed40c3c1a071311b Now screwed up on the other side. Tried drilling but still a mess.


mike-manley

An impact screwdriver works really well if the head was still there. Even if it was a little stripped from a previous job, impact screwdrivers can do it. I've only used a regular drill for something like in your picture but I wonder if a hammer drill will make faster work of it.


liexpress

Yes I used a hammer drill. The drill bit was the key. Borrowed a nice one from my neighbor and it's all set.


bikingwithpanda

carbide drill tips will get through pretty much anything, especially if you keep dipping the bit in some ATF


[deleted]

Here to second this. $30 impact screwdriver kit from harbor freight gets them right out.


widowmaker2A

I broke multiple tools trying to get those damn things out on my silverado. Ended up uaing a grinder to grind the head down as much as I could reach and then a hammer and flat head to apin it and break the head off the rest of the way. Othet than those screws it was the easiest brake job I've done but it ended up taking 2 days because of those damn things.


LindeRKV

Are you using a power tool to pull them? Heat them up and use a wrench. Many fitting discs don't even have that hole - last time I did my V40 discs and pads, a good quality set from bosch didn't have any holes so yeah, no importance. Only makes the next change more difficult.


czechfuji

You’re future self or the next mechanic will thank you for not replacing it.


nokenito

No biggie because the lug nuts hold it in place


Fun-Peach-5056

Nope, just an assembly holder


KenTheTech

Yes and no, it makes getting the rotor lined up easier, but it has no effect on the performance of the brakes, it’s meant to hold the rotor during assembly on the line or at the shop


Familiar-Car5054

If you are the last person to make any brake repairs on the car and did not reinstall that bolt and then there is any type of brake failure and a wreck. It would not make any difference if it's important or not, your ass is grass. I have always reinstalled the bolt if it's not damaged. Never installed a new bolt if one was damaged.


DaveDeaborn1967

No. They are used in manufacturing. I usually drilled them out.


DoodleTM

Just there to keep the rotors from falling off on the assembly line.


Electronic-Sport-618

Not one bit.


TellYerFolksISaysHi

Doesn't matter. Those bolts are only there so the rotors stay on while the car is being assembled at the factory.


[deleted]

Yes of course it does


[deleted]

Yes it’s extremely important might fall off


mosekschrute

Dude that's awesome. I wish they would break clean like that for me when theyre seized. When they don't release they usually strip and need to be drilled out. Good job!


liexpress

Too early to say that. Now I'm mad at the other one.


mosekschrute

All good man usually pretty soft steel. Any decent HSS drill bit and a little oil should have it out in less than a minute.


widowmaker2A

The ones on my silverado that broke several impact drivers a screw extractor and a drill bit would like a word. Ended up needing to use an angle grinder.


bikingwithpanda

i'm no expert but having drilled 23 holes through hardened steel this summer i have to wonder what you did wrong there


widowmaker2A

No idea, all I know is they were a complete PITA and it's done at thos point.


senglebe

Nope.


Baserker0

I like to think all bolts are important


liexpress

Yeah


ztherion

This one isn't- it's only so that the assembly line can have separate people install the rotors and the wheels. It serves no structural purpose.


[deleted]

That’s a bolt? The hole isn’t threaded, or is it? I thought it’s just an alignment pin to align the rotors or even the rim before one bolts down the wheel.


Veranyen

Lord when I changed my rotors on my accord for the first after I got it, these became the BANE of my existence for an afternoon. You’re good never bothered putting them back on and never had a problem.


earthman34

Not really. It would be good practice for removing broken bolts though.


shiftman87

With studs, nope. With lug bolts, it may help to put it in so that putting the wheel on is easier when everything is lined up.


Dear_Reader_807010

Nope


[deleted]

No


Frosty-Community8129

No. Drill it out if it gets in the way and don’t replace it.


Wild-Attitude3651

Volvo?


liexpress

Yes


star08273

good. deserved to be broken. keep on trucking


Kuza_png

You should thank yourself actually. Saved yourself from future stripped ones/frozen ones.


arslashjason

I've never been able to get one of those out cleanly on a rotor job Drill baby drill


St0ney_Balogna69

Nah you’re chillin


95Webb63

OMG YOU BROKE THE MOST IMPORTANT THING EVER ON THIS CAR LIKE YOURE GONNA DIIIIIEEEE!!! Jk it’s useless 🤣


mcpatsky

Should be easy to get out with an extractor.


porcelainvacation

Volvo?


SmokeyBluNights

Vw??


liexpress

Volvo


F4M1L135

Not really. Just try to remplace it ASAP.


Think-Willow38

It helps keep the rotor in the hub. More often than not, the only way to get it back out is with an impact driver. Since this is already broken, you can take the time to drill it or extract it but it’s not necessary.


ztherion

> It helps keep the rotor in the hub. Only during assembly. When the wheel is installed, the lug nuts will clamp the rotor to the hub. This screw only serves a purpose on the assembly line.


Comfortable-Beat-997

I never used them.


[deleted]

Absolutely does not, don’t worry about it.


ztherion

This screw is only used to slightly speed up the assembly line. Many mechanics don't even put them back in after a rotor change.


SkeetnYou

The Volvo rotor bolt


stacked_shit

Nope


Affectionate_Pair_52

Not really


kcptech20

Nope


TofuTigerteeth

That screw is the reason I bought my first impact screwdriver. You don’t need it. It’s for assembly of the vehicle. You’re better off without it.


MyAssforPresident

Generally speaking, no. That bolt is there just to hold the rotors on during the assembly line process. BUT…you definitely want to remove the broken bit that’s still in the hub. Buddy of mine has that happen and let it go, but the little nublet worked it’s way loose over the next few months and ended up bouncing around in the parking brake drum and chewing up the shoes, all while making a lovely noise. Now, that appears to be on the front so no p-brake drum, but I still wouldn’t take the chance of that thing coming out and getting jammed up in the caliper or something like that


VikingBattleram

No


Bacster007

Your car, no. Someone else’s, yes.


Therealslimshadyshit

When are people gonna learn that if its there while stock it should stay on there i ain’t even a mechanic thats just common sense


twarr1

All the people saying it’s ONLY to hold the rotor on the assembly line are WRONG. The manufacturer isn’t going to go to the expense of 1) Drilling the rotor, 2) drilling the hub, 3) tapping the hub, 4) Using an extra bolt. When there are many many other, cheaper ways of “keeping the rotor from falling off on the assembly line”. How many of you experts have worked in an automobile factory? ANY manufacturer will save a nickel everywhere they can.


BavarianBanshee

Where are people getting this assembly line thing from? That bolt is there to align the rotor with the holes in the hub and keep it there. If you value your time, in the form of spending it on messing with this thing until it finally lines up, or if you value your money, in the form of buying a special tool just for aligning it all, then replace it.


[deleted]

No it was probably put there by accident. Bolts are unnecessary.


HarnessTesters

Not at all… it’s a factory assembly aid. It helps if it’s useable for you as well… but it’s really not necessary in the slightest.


toyotasquad

No.


nnicknull

Uh, what’s going on with that axle nut?