OT car wheel hub screws

[hubops]

Just found these screws loose & missing when changing over to summer tires -

- I don't even know what they do .. .. nor what they're called ? so I can look them up.

John T.

[Bob F]

You use screw bolts into those holes to remove the drum from the parking brakes if you cannot release the shoes sufficiently to allow it to be easily pulled off.

[hubops]

Ha. Ha. Ha. Any serious answers are appreciated. John T.

[Bob F]

Ummmm?

That was a serious answer.

With the unnecessary word "use" accidentally left in from an edit.

Screwing bolts into those threaded holes pushes against the hub to force the drum/disk off. You should see that the threaded holes do not continue into the hub. They can only push against it.

[micky]

Bob has a great sense of humor, however this time it was misplaced. The screws that go there press the brake disk against the inner half off the caliper. Without them, the brakes may not work. Please get it fixed soon.

[hubops]

Sheeesh. John T.

[Bob F]

Have you looked at the video in my last reply?

[Clare Snyder]

They keep the rotor or drum from falling off on the assembly line. Not a bad idea to keep them in place but they are not at all critical

[Clare Snyder]

Actually on SOME drums the hole in the drum WAS threaded - on Japanese cars thery were M8. On those vehicles they WERE a built-in drum puller. However, on the picture shown they are NOT threaded, and the holes are countersunk, and they ARE just a fixture to hold the rotors/drums on the hub on the assembly line

[Clare Snyder]

Not so

[hubops]

Yep. It seems to deal with drum brakes. John T.

[Xeno]

In total agreement with you here. I've removed more drums and discs than I care to remember and those threaded holes are a blessing.

I'd prefer to see them blanked off with a dummy cs screw just to keep the threads clean and clear. The dummy cs screw doesn't need to retain anything, just prevent those threads gunking up.

[Xeno]

Noticed the countersinking.

Also if the wheel comes off. Not so much with a disc as that will be constrained by the caliper.

Recently removed the rear drums on a Toyota Yaris - 2 threaded holes, no screws in them. When I was refitting them, I was careful to ensure that the threaded holes were adjacent a solid chunk of the axle flange

[Bob F]

More important is making sure the adjustment hole is lined up with the correct hole in the hub. The others will be right then.

[Bob F]

Or disk/drums like my 04 Sienna rear brakes, or like yours. I can see the parking brake cable coming in behind the disk at 4 o'clock in your pic. If the holes are not threaded, I guess Clare is right.

[Xeno]

Done from (through) a slot in the backing plate. That aperture has a rubber bung in it.

[Bob F]

I've never seen one like that. I have always done it through the hole in the drum. With a rubber plug.

[Xeno]

I saw the countersink but, on my small screen, couldn't tell if the holes were threaded. Eyesight isn't what it used to be! :-(

[Xeno]

The Yaris was the same as this one.

Back in the 70s, the backing plate hole for adjustment was the norm. For the most part, it was brought about by the inclusion of self adjusters. If you adjusted them too tight, the self adjuster acted as a ratchet and prevented you loosening the adjuster back off. That then necessitated the use of a second tool (long thin screwdriver) to push the self adjuster plate away whilst backing off the adjuster.

[hubops]

My brother raised the question - could a backed-out screw interfere / affect the wheel seating flat against the disc ? .. it seems possible - I'll need to check that, next time I have a wheel off .. John T.