WAS: 05 Elantra GT Rear Disk Brakes Question
 

Just to update and thank all those that responded and helped.
OK, last night I changed the rear pads. I took it for a quick test
drive. No question it is better. I would say that it is close to where
it was when new. The pedal is still lower than I think it should be,
but it has always been that way. I will drive it further later
today...but so far it seems to have done the trick. (You hit it on the
head Mike..I am happy!). And Hyundaitech thank you for your continued
help for everyone here including me.
Just for the record, the part I still don't get is why this should
happen with about 50% wear on the pads. After removing them I would
say I had 60% left on the pasenger side and maybe 45-50 on the driver
side. Just does not seem right, but it is certainly a simple fix...and
only $40 (could have even got brakes for $30). In he future I guess I
will just change the fronts and rears at the same time which would be
approx every 18-20K.
Thanks all. I'll report back if I go through a brick wall tonight and
change my mind about the brakes working so good. :-)
Now I bring in my 03 for the timing belt next week (not the dealer)
and buy a new Sonata probably...and give the 03 to my son. I will miss
that car. I truly love the 03, the 05 just never felt as "tight" a car
in every way...just a much more solid car.
Thanks all.

Re: WAS: 05 Elantra GT Rear Disk Brakes Question
 

I cannot think of a logical explanation for why replacing the pads would
change the pedal height. I'm not disputing your finding; I just cannot
think of a reason why it should be so.

Re: WAS: 05 Elantra GT Rear Disk Brakes Question
 

On Sat, 14 Jul 2007 12:30:05 -0400, "hyundaitech"
<notpublic@not.public.com> wrote:

>I cannot think of a logical explanation for why replacing the pads would
>change the pedal height. I'm not disputing your finding; I just cannot
>think of a reason why it should be so.

Very strange I admit. Especially considering the fact that the pads
really weren't all that worn. I still think it is too low, but it is
not spongy at all anymore and at least a little higher. Weird.

Re: WAS: 05 Elantra GT Rear Disk Brakes Question
 

hyundaitech wrote:
> I cannot think of a logical explanation for why replacing the pads would
> change the pedal height. I'm not disputing your finding; I just cannot
> think of a reason why it should be so.

Exactly. Brake systems are supposed to be self adjusting. There should
be NO difference in brake pedal height between new pads and pads that
are completely worn out, and that's exactly the way every car I've owned
has been, including my Elantra. The fact that your pedal height changes
indicates that there is something wrong with your brake system and
changing pads more frequently than necessary is NOT the answer.

Considering that the self-adjustment is a function of fluid flowing from
the reservoir into the master cylinder and ultimately into the calipers,
I suspect that there is a blockage between the reservoir and the master
cylinder. Perhaps pushing the rear pistons (and the extra fluid) in
dislodged it, but since the pedal still seems low, I suspect that's not
the case. I wouldn't trust the brake system until it's been thoroughly
checked out and flushed from the calipers up. Your car is NOT fixed, you
merely masked one of the symptoms of the problem.

Re: WAS: 05 Elantra GT Rear Disk Brakes Question
 

On Sun, 15 Jul 2007 02:26:16 GMT, Brian Nystrom
<brian.nystrom@verizon.net> wrote:

>hyundaitech wrote:
>> I cannot think of a logical explanation for why replacing the pads would
>> change the pedal height. I'm not disputing your finding; I just cannot
>> think of a reason why it should be so.
>
>Exactly. Brake systems are supposed to be self adjusting. There should
>be NO difference in brake pedal height between new pads and pads that
>are completely worn out, and that's exactly the way every car I've owned
>has been, including my Elantra. The fact that your pedal height changes
>indicates that there is something wrong with your brake system and
>changing pads more frequently than necessary is NOT the answer.
>
>Considering that the self-adjustment is a function of fluid flowing from
>the reservoir into the master cylinder and ultimately into the calipers,
>I suspect that there is a blockage between the reservoir and the master
>cylinder. Perhaps pushing the rear pistons (and the extra fluid) in
>dislodged it, but since the pedal still seems low, I suspect that's not
>the case. I wouldn't trust the brake system until it's been thoroughly
>checked out and flushed from the calipers up. Your car is NOT fixed, you
>merely masked one of the symptoms of the problem.

I agree. That is why I was mad at the dealer...I brought it in for low
pedal (to the floor) and their only answer (in writing I might add)
was changing the rear pads. I checked the shop manual, checked all
troubleshooting guides...not one mentioned pads for a low pedal..not
even on the list of possibilities. I will be complaining to the
dealer. Having said tha, the pedal is still low, but not as low as
before replacing the pads...but the brakes feel much better I have to
admit. Thanks.

Re: WAS: 05 Elantra GT Rear Disk Brakes Question
 

jtees4 wrote:
> On Sun, 15 Jul 2007 02:26:16 GMT, Brian Nystrom
> <brian.nystrom@verizon.net> wrote:
>
>> hyundaitech wrote:
>>> I cannot think of a logical explanation for why replacing the pads would
>>> change the pedal height. I'm not disputing your finding; I just cannot
>>> think of a reason why it should be so.
>> Exactly. Brake systems are supposed to be self adjusting. There should
>> be NO difference in brake pedal height between new pads and pads that
>> are completely worn out, and that's exactly the way every car I've owned
>> has been, including my Elantra. The fact that your pedal height changes
>> indicates that there is something wrong with your brake system and
>> changing pads more frequently than necessary is NOT the answer.
>>
>> Considering that the self-adjustment is a function of fluid flowing from
>> the reservoir into the master cylinder and ultimately into the calipers,
>> I suspect that there is a blockage between the reservoir and the master
>> cylinder. Perhaps pushing the rear pistons (and the extra fluid) in
>> dislodged it, but since the pedal still seems low, I suspect that's not
>> the case. I wouldn't trust the brake system until it's been thoroughly
>> checked out and flushed from the calipers up. Your car is NOT fixed, you
>> merely masked one of the symptoms of the problem.
>
> I agree. That is why I was mad at the dealer...I brought it in for low
> pedal (to the floor) and their only answer (in writing I might add)
> was changing the rear pads. I checked the shop manual, checked all
> troubleshooting guides...not one mentioned pads for a low pedal..not
> even on the list of possibilities. I will be complaining to the
> dealer.

If you don't get anywhere with them, let them know that you'll be
contacting Hyundai directly and then do so. Hyundai is very responsive
to customer complaints, but their dealers vary considerably in that regard.

> Having said tha, the pedal is still low, but not as low as
> before replacing the pads...but the brakes feel much better I have to
> admit. Thanks.

That makes sense. By installing new pads, you've pushed more fluid into
the system, which would have the effect of pushing the brake pedal upward.

Have you tried pulling outward on the pedal? I'm curious what would
happen if you do so.

Re: WAS: 05 Elantra GT Rear Disk Brakes Question
 

On Mon, 16 Jul 2007 16:33:16 GMT, Brian Nystrom
<brian.nystrom@verizon.net> wrote:

>jtees4 wrote:
>> On Sun, 15 Jul 2007 02:26:16 GMT, Brian Nystrom
>> <brian.nystrom@verizon.net> wrote:
>>
>>> hyundaitech wrote:
>>>> I cannot think of a logical explanation for why replacing the pads would
>>>> change the pedal height. I'm not disputing your finding; I just cannot
>>>> think of a reason why it should be so.
>>> Exactly. Brake systems are supposed to be self adjusting. There should
>>> be NO difference in brake pedal height between new pads and pads that
>>> are completely worn out, and that's exactly the way every car I've owned
>>> has been, including my Elantra. The fact that your pedal height changes
>>> indicates that there is something wrong with your brake system and
>>> changing pads more frequently than necessary is NOT the answer.
>>>
>>> Considering that the self-adjustment is a function of fluid flowing from
>>> the reservoir into the master cylinder and ultimately into the calipers,
>>> I suspect that there is a blockage between the reservoir and the master
>>> cylinder. Perhaps pushing the rear pistons (and the extra fluid) in
>>> dislodged it, but since the pedal still seems low, I suspect that's not
>>> the case. I wouldn't trust the brake system until it's been thoroughly
>>> checked out and flushed from the calipers up. Your car is NOT fixed, you
>>> merely masked one of the symptoms of the problem.
>>
>> I agree. That is why I was mad at the dealer...I brought it in for low
>> pedal (to the floor) and their only answer (in writing I might add)
>> was changing the rear pads. I checked the shop manual, checked all
>> troubleshooting guides...not one mentioned pads for a low pedal..not
>> even on the list of possibilities. I will be complaining to the
>> dealer.
>
>If you don't get anywhere with them, let them know that you'll be
>contacting Hyundai directly and then do so. Hyundai is very responsive
>to customer complaints, but their dealers vary considerably in that regard.
>
>> Having said tha, the pedal is still low, but not as low as
>> before replacing the pads...but the brakes feel much better I have to
>> admit. Thanks.
>
>That makes sense. By installing new pads, you've pushed more fluid into
>the system, which would have the effect of pushing the brake pedal upward.
>
>Have you tried pulling outward on the pedal? I'm curious what would
>happen if you do so.

I just sent a letter off to the service managaer at the dealer. I will
give him a couple of days to respond. Next will be a letter to Hyundai
directly. This morning my wife was on her way to work and she said
that it got bad again...and she usually tells me something isa fine
even when it isn't..so I'll assume it's bad. When she gets home I will
try pulling up on the brake pedal...never tried that. I'll let you
know.

Re: WAS: 05 Elantra GT Rear Disk Brakes Question
 

On Mon, 16 Jul 2007 16:33:16 GMT, Brian Nystrom
<brian.nystrom@verizon.net> wrote:

>jtees4 wrote:
>> On Sun, 15 Jul 2007 02:26:16 GMT, Brian Nystrom
>> <brian.nystrom@verizon.net> wrote:
>>
>>> hyundaitech wrote:
>>>> I cannot think of a logical explanation for why replacing the pads would
>>>> change the pedal height. I'm not disputing your finding; I just cannot
>>>> think of a reason why it should be so.
>>> Exactly. Brake systems are supposed to be self adjusting. There should
>>> be NO difference in brake pedal height between new pads and pads that
>>> are completely worn out, and that's exactly the way every car I've owned
>>> has been, including my Elantra. The fact that your pedal height changes
>>> indicates that there is something wrong with your brake system and
>>> changing pads more frequently than necessary is NOT the answer.
>>>
>>> Considering that the self-adjustment is a function of fluid flowing from
>>> the reservoir into the master cylinder and ultimately into the calipers,
>>> I suspect that there is a blockage between the reservoir and the master
>>> cylinder. Perhaps pushing the rear pistons (and the extra fluid) in
>>> dislodged it, but since the pedal still seems low, I suspect that's not
>>> the case. I wouldn't trust the brake system until it's been thoroughly
>>> checked out and flushed from the calipers up. Your car is NOT fixed, you
>>> merely masked one of the symptoms of the problem.
>>
>> I agree. That is why I was mad at the dealer...I brought it in for low
>> pedal (to the floor) and their only answer (in writing I might add)
>> was changing the rear pads. I checked the shop manual, checked all
>> troubleshooting guides...not one mentioned pads for a low pedal..not
>> even on the list of possibilities. I will be complaining to the
>> dealer.
>
>If you don't get anywhere with them, let them know that you'll be
>contacting Hyundai directly and then do so. Hyundai is very responsive
>to customer complaints, but their dealers vary considerably in that regard.
>
>> Having said tha, the pedal is still low, but not as low as
>> before replacing the pads...but the brakes feel much better I have to
>> admit. Thanks.
>
>That makes sense. By installing new pads, you've pushed more fluid into
>the system, which would have the effect of pushing the brake pedal upward.
>
>Have you tried pulling outward on the pedal? I'm curious what would
>happen if you do so.



I faxed a letter to the dealer about 3PM. Got a call from the service
manager around 5PM. Not bad. She wants to personally see my car, I am
bringing it in Thursday. She was very nice and apologetic and asked
for another chance at the low brake pedal thing. So far so good. Maybe
something will get done after all. I'll let yo all know later in the
week.

Re: WAS: 05 Elantra GT Rear Disk Brakes Question
 

>> Having said tha, the pedal is still low, but not as low as
>> before replacing the pads...but the brakes feel much better I have to
>> admit. Thanks.

>That makes sense. By installing new pads, >you've pushed more fluid into

>the system, which would have the effect of >pushing the brake pedal
upward.

It's put more fluid in the reservoir, but the amount of fluid in the
cylinder portion should be the same. I don't see the link between more
fluid in the reservoir and a higher pedal.

I'll agree that we have less fluid in the calipers. But it should still
take the same amount of pedal travel to apply the same braking force.

Re: WAS: 05 Elantra GT Rear Disk Brakes Question
 

hyundaitech wrote:
>>> Having said tha, the pedal is still low, but not as low as
>>> before replacing the pads...but the brakes feel much better I have to
>>> admit. Thanks.
>
>> That makes sense. By installing new pads, >you've pushed more fluid into
>
>> the system, which would have the effect of >pushing the brake pedal
> upward.
>
> It's put more fluid in the reservoir, but the amount of fluid in the
> cylinder portion should be the same. I don't see the link between more
> fluid in the reservoir and a higher pedal.

If there is a blockage between the reservoir and the master cylinder
such that fluid cannot flow between them, the brake pedal engagement
point will get lower as the pads wear, since no fluid can flow into the
system to compensate for pad wear. When you replace the pads, it will
push the pedal engagement point back up to where it was.

> I'll agree that we have less fluid in the calipers. But it should still
> take the same amount of pedal travel to apply the same braking force.

The amount travel doesn't change, just the engagement point.

OTOH, since his wife is reporting the same problem again, it sounds like
it may be a bad master cylinder.

Re: WAS: 05 Elantra GT Rear Disk Brakes Question
 

>If there is a blockage between the reservoir >and the master cylinder
>such that fluid cannot flow between them, the >brake pedal engagement
>point will get lower as the pads wear, since no >fluid can flow into the

>system to compensate for pad wear. When you >replace the pads, it will
>push the pedal engagement point back up to >where it was.

I saw something like this once where the reservoir cap wasn't vented
properly. Applying the pedal pushed the pads against the rotors, and
releasing sucked them away (about 1/4" if I remember right). Removing the
master cylinder cap made the problem go away. Replaced cap. No more
problems.

(Of course, I don't recommend driving around with your master cylinder cap
off to test this theory. I have the distinct advantage of performing tests
on a lift.)

Re: WAS: 05 Elantra GT Rear Disk Brakes Question
 

hyundaitech wrote:
>> If there is a blockage between the reservoir >and the master cylinder
>> such that fluid cannot flow between them, the >brake pedal engagement
>> point will get lower as the pads wear, since no >fluid can flow into the
>
>> system to compensate for pad wear. When you >replace the pads, it will
>> push the pedal engagement point back up to >where it was.
>
> I saw something like this once where the reservoir cap wasn't vented
> properly. Applying the pedal pushed the pads against the rotors, and
> releasing sucked them away (about 1/4" if I remember right). Removing the
> master cylinder cap made the problem go away. Replaced cap. No more
> problems.
>
> (Of course, I don't recommend driving around with your master cylinder cap
> off to test this theory. I have the distinct advantage of performing tests
> on a lift.)

Now that makes sense and it would be easy for him to test.