Replacing a brake rotor

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SearchMaster

Diamond Member
Jun 6, 2002
7,791
114
106
ack!

Stripped a screw.

I f'ing hate phillips head screws. Why???? Why do we still use them?????

They're the worst screw design ever.

Anyways, got it out.

Need a replacement, of course, will get tomorrow...

I'm hoping I can find it at...Lowes?
If it's just the retaining screw that stripped, you don't HAVE to replace it. As mentioned before they are a PITA anyway.

I've never looked but I would assume it's a metric screw because (a) it's a Korean car, and (b) most small screws on cars are metric (M6 or M8 probably). So that may make it a bit harder to find, though Autozone/NAPA/etc. likely carry them. I stripped one once and never replaced it, but otherwise I do replace them when they're in good shape.
 

JCH13

Diamond Member
Sep 14, 2010
4,981
66
91
Phillips are used as it easier for automated tools or for an assembly line worker to use. The bit just pops into the screwhead. With slotted screws, it takes much more time to get the tool into position and the bit can easily slip out and ruin the screw. If your Phillips screw was extremely tight, then you should have sprayed some penetrating oil on it first, then be sure the head was oil free. Use of the proper number Phillips bit is important as well. They also make what is called a Pozi Drive Bit ... it has serrations at the very tip where it fits into the screw and it will grab it much better than a regular bit. Also if you used a screwdriver, the better ones are the ones with the Black Tips as they are harder.

I don't mean to come down too hard on you, but I think I need to correct some factual issues in your post. Please don't take this personally, I have made many of these mistakes myself.

Phillips are terrible IMO. They do auto align better than a flat-head, but they are designed so that the bit 'cams out' before anything strips, which is why you have to apply so much forward force to keep the bit seated. Even then it hardly does its job because camming out tends to damage the screw and the bit anyway. Torx, allen socket, square drive, Frearson, etc. are all far superior to philips IMO.

Wiki article on 'camming out'

The 'hammer' type impact driver someone else pictured is ideal for removing philips bits that are stuck because the force from the hammer strike will almost always completely counteract the 'cam out' force from the bit.

Wiki article on impact drivers

Drive bits that are black (typically black oxide coated) are NOT harder than other bits, quite the opposite in fact. They are generally designed for use in impact drivers and thus are intentionally NOT hardened, so they don't shatter. They will generally be leaps and bounds better than your run-of-the-mill shitty powder metal bits, but not because they are harder. They will be made of stronger, more ductile materials (i.e. no chrome and different heat treatment) and typically are reinforced in key areas. Same goes for impact sockets.

There are, of course, regular bits that are just painted black. They are still pretty terrible. You'll get what you pay for, so don't cheap out.

Pozidriv bits aren't designed to fit a philips screw, they are designed to fit a pozidriv bit. The two are very easy to confuse, but they are different. Pozidriv bits won't fit a phillips screw properly, and phillips bits won't fit a pozidriv screw properly. They should not be interchanged. Using one in the other will typically cause damage.

Wiki article on pozidriv bits (and other drive styles)

You probably meant to call it an anti-slip phillips bit, but that is a very different thing and thus has a different name. They can help a bit (rimshot) but a hammer-style impact tool is a much better solution for this problem.

Pic of anti-slip phillips bit:
1RBP2.jpg



As for removing a stuck screw, I agree that penetrating oil is good and making sure the screw head is clean is very important (helps reduce cam-out forces). As is using the right size bit, this is quite frequently a #3 phillips (usually the biggest bit/driver kicking around) on brake retaining screws.
 

bruceb

Diamond Member
Aug 20, 2004
8,874
111
106
The bit you pictured is what I was referring to. And I agree, the other types of fasteners you mention are better, but you almost never see them on brake rotors. As to the black type phillips, on bits that go into a hammer driver, you may be correct. But so far, I have found that screwdrivers with the black tips are far better than the chrome tipped versions. Also, if the vehicle is Japanese or built to Metric specs, then a normal American Phillips driver just will not fit properly. It will be close, but not perfect and will slip if extremely tight. They do make Metric Spec Phillips bits and screwdrivers. Japanese use a special spec called JIS .. looks like Philliips, but not quite.
http://www.instructables.com/id/Whe...lips/step10/JIS-Japanese-Industrial-Standard/
 

JCH13

Diamond Member
Sep 14, 2010
4,981
66
91
My comments about phillips being terrible are just me ranting :$

Interesting about the JIS drive, I didn't know that was a thing. I've always had a #3 fit quite nicely and typically remove each bolt without issue, unless it's really rusted in there.
 

desura

Diamond Member
Mar 22, 2013
4,627
129
101
So I don't have to replace the screw? Just one will be okay? Finding a replacement for this little screw is a huge PITA...
 

iamwiz82

Lifer
Jan 10, 2001
30,772
13
81
um, it is one of the two screws holding in the brake rotor.

I have had 37 cars in the past 14 years and not one has had a screw to hold the rotor on. That is usually a Honda thing.

No, you do not need the screw. It was there only for manufacturing the car, easier to build it.
 

SearchMaster

Diamond Member
Jun 6, 2002
7,791
114
106
This photo is from AveoForum.com so I assume it's an Aveo rotor...

If it's one of the circled screws, those are the retaining screws and are not necessary.

Think about it - would you trust a screw that size to bear the torque of stopping a 2500+ pound car? Again, if it makes you feel better you can likely pick them up at Autozone - they seem to carry M6 and M8 and are called "Disc Retaining Screws" (part numbers 13823 and 13824). The M6's are listed as for Honda on their website and the M8's are listed as Ford/Mazda - buy a package of each if it makes you feel better ($3 each package) :).

aveo_rotor.png
 
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JCH13

Diamond Member
Sep 14, 2010
4,981
66
91
Replacements like that are good to get from a source like BelMetric, McMaster Carr, or your local hardware store with a good fastener selection.
 

waggy

No Lifer
Dec 14, 2000
68,143
10
81
It's not a hard job. Are you sure you need new rotors, you may be able to resurface the old ones if they are warped but there is thickness left in them. It would be maybe $10 per rotor for that.

$10? NOBODY around here will resurface them for under $40 EACH. fuck that at that price i just buy new ones.
 

Ban Bot

Senior member
Jun 1, 2010
796
1
76
Thanks for the informative thread. I need to replace the rotors on our 2006 Chevy Uplander. I am considering doing it with some help as the shop wanted about $1000 for front and back.

What is usually considered a "fair" shop price for front and rear rotors?

Also, it seems the Uplander benefits from heavier duty rotors but those who have done such didn't leave a part number. How would one go about researching if a non-stock rotor SKU would be compatible?
 

996GT2

Diamond Member
Jun 23, 2005
5,212
0
76
OP do yourself a favor before you start and get a bottle of PB blaster. Will make removing rusted on bolts MUCH easier.

blaster003%20023.jpg
 

mvbighead

Diamond Member
Apr 20, 2009
3,793
1
81
Thanks for the informative thread. I need to replace the rotors on our 2006 Chevy Uplander. I am considering doing it with some help as the shop wanted about $1000 for front and back.

What is usually considered a "fair" shop price for front and rear rotors?

Also, it seems the Uplander benefits from heavier duty rotors but those who have done such didn't leave a part number. How would one go about researching if a non-stock rotor SKU would be compatible?

Yikes. That's a high quote.

To me, figure roughly $60 per pair of pads for a total of $120. Figure $50 per rotor or so for a total of $200. Grand total of parts is roughly $320. Add about 2 hours of labor at $80 a pop, and you should be somewhere around $500.

Rockauto is a great place to find matches, and a lot of times I use prime on Amazon to order instead cross matching part numbers on Rock to be sure.

I did a quick figure, and found Raybestors rotors and Wagner ceramic pads for $294 shipped on RockAuto for your vehicle. I'd usually cross compare like I said, but RockAuto has one of the best part finders you can use.
 

JCH13

Diamond Member
Sep 14, 2010
4,981
66
91
Thanks for the informative thread. I need to replace the rotors on our 2006 Chevy Uplander. I am considering doing it with some help as the shop wanted about $1000 for front and back.

What is usually considered a "fair" shop price for front and rear rotors?

Also, it seems the Uplander benefits from heavier duty rotors but those who have done such didn't leave a part number. How would one go about researching if a non-stock rotor SKU would be compatible?

My S/O was quoted about a grand to do front and rear pads and rotors on her Civic from a dealer with $65/hr labor rate. I did the work myself with around $400 in parts.

OP do yourself a favor before you start and get a bottle of PB blaster. Will make removing rusted on bolts MUCH easier.

http://www.expeditionexchange.com/blaster/blaster003 023.jpg

Kroil or acetone+atf FTW. Either one is way better than PB Blaster in my experience.
 

Meghan54

Lifer
Oct 18, 2009
11,684
5,228
136
Yikes. That's a high quote.

To me, figure roughly $60 per pair of pads for a total of $120. Figure $50 per rotor or so for a total of $200. Grand total of parts is roughly $320. Add about 2 hours of labor at $80 a pop, and you should be somewhere around $500.

Rockauto is a great place to find matches, and a lot of times I use prime on Amazon to order instead cross matching part numbers on Rock to be sure.

I did a quick figure, and found Raybestors rotors and Wagner ceramic pads for $294 shipped on RockAuto for your vehicle. I'd usually cross compare like I said, but RockAuto has one of the best part finders you can use.


That's pretty much what I do.....RockAuto for searching the part no., Amazon for the part with Prime shipping. RockAuto can and usually has better prices than Amazon, that is until you add in shipping at RockAuto. Then Amazon is usually cheaper, esp. if using Prime. And sometimes you can catch very cheap prices on some parts. Got a pair of Raybestos front rotors for a '95 Volvo 940 Turbo for $9.95/ea., shipped from Amazon. Couldn't touch that price anywhere else.