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Hyundai Tucson - self-adjusting brakes?

Why are you doing that in the first place? It serves no purpose. Did you see someone do that or did someone tell you to do it? When I read statements like that I wonder what other silly ideas the person has been told by someone. Arvin if you are doing other things that you question post away and find out if they are correct or needless actions.

• Why are you doing that in the first place? It serves no purpose. Did you see someone do that or did someone tell you to do it?

I did it ever since I found that doing it resulted in better braking of my vehicle (i.e. the vehicle would stop quicker whenever I did this). No one told me to do it, nor do I know why it came to me to do that in the first place.

• Arvin if you are doing other things that you question post away and find out if they are correct or needless actions.

Thanks! I certainly will. So far I’ve found alot of helpful, smart people on here.

Here’s an example of an owner’s manual explaining this procedure.

http://www.fordservicecontent.com/Ford_Content/catalog/owner_guides/96f12og1e.pdf

1996 Ford F150 Owner’s Manual

"Rear Drum Brakes
The rear drum brakes are self-adjusting.
Automatic adjustment occurs when the brakes
are applied while “backing up.” If normal
operation does not include much backing, adjust
the brakes when they seem “low,” using the
procedure under If Brakes Do Not Grip Well "

Thanks for supplying that information :slight_smile:

I tried doing that on my disc-front, drum-rear Corolla and didn’t notice any difference. Explain what you mean by “locks up”. I could imagine in some vehicle’s brake configurations the pedal might feel a little higher and harder when the e-brake is applied, but I wouldn’t describe that as “locking up”.

Yeah, I suppose the feeling I get from mine is that it feels higher and harder – but as for “locks up”, what that means is that I park my vehicle (with gear set to park of course), car turned off (but still able to have the radio on), e-brake is pulled up all the way, and then I press down on the brake pedal until you can’t press down on it anymore – that’s what I mean by “locks up”.

As I’ve mentioned before, I’m not a mechanic, or a gear-head, so I have no idea what the proper terms are for these things.

I wasn’t able to find any info in my 2007 Hyundai Tucson user manual relating to self-adjusting brakes.

Again, why would you do that? and if you did that, as you said, you “can’t press down on it anymore”, that is NOT “locked up”, that is merely the brake fully applied.

OR do you mean you pump the brakes? that is different from just pressing the pedal down.

You stop vehicle-put it in park-set parking brake and you are done. The brakes are out of the picture no matter how many times you press on brake pedal.

Not all vehicles have a self-adjusting feature. As posted above, disc brakes don’t need it. And parking brakes on disc brake all around vehicles in many configurations don’t need a self-adjusting feature either. As I recall a poster above researched this for your car and determined it doesn’t have a self adjusting feature, right?

What you are doing is bleeding the vacuum off from the power brake reservoir. That makes the brakes feel like they engage higher up. It will do exactly the same thing if you don’t set the parking brake.

Disc brakes are self adjusting, there is no need to mention this in the owners manual, most cars now have disc brakes and do not need adjusting.

Maybe we’re saying the same thing here?
The piston seal tries to follow the piston motion. As an example, one side of the seal is captive in the caliper bore, the other rubs against the piston and is dragged forward slightly along with it. This creates tension in the seal and it helps to retract the piston slightly once the hydraulic pressure is relieved. Just one example, doesn’t matter if the seal is seated in a groove on the piston or in the cylinder bore.

There is almost always some run-out in the rotor as well and this motion during rotation helps push the piston back into the bore slightly as well.

don’t most manufacturers call them ‘Parking Brakes’, not ‘Emergency Brakes’?

Unrelated to the OP’s question, but I have to be very deliberate with that in my fleet- as the vast majority of my vehicles do not have “Park” in the transmission. Park is the transmission in neutral, and Parking Brake applied. When it is called an “Emergency Brake”, drivers don’t always get the idea that it has to be applied to park.

Yes…it’s a better name and I need to switch (old habit).

A final note…for parking brakes that use the rear calipers (no internal shoes), there is a self-adjusting mechanism inside the piston that actuates as the pads wear down.

I think the term “emergency brake” is more commonly used in europe . . . ?

Sounds like you’re describing an Allison automatic transmission . . .

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yep :slight_smile:

adding to make 10 chatracters

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The term Emergency Brake goes back to the time when braking systems were a lot less reliable. If your hydraulic brakes failed you could us your mechanically operated emergency brake. Prior to the late forties automatic transmissions were only available on very, very few cars. Most people would leave their car in gear when parked and not use the emergency brake.

As far as your brake pedal ‘locking up’ with the engine off the brakes are power brakes, the engine has to be running. Brakes will still operate with the engine off but require a LOT more pedal pressure.