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  #1  
Old 11-22-2004, 02:28 PM
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Brake pedal problem, gilly...

My brake pedal has been traveling too far toward the floor. I ignored it because I knew the rear pads/rotors were thin. Well, I replaced them and the pedal has improved, but not much. It's not "spongy" feeling, it just travels too far before it bottoms out (If I leave the other foot under the pedal, it will touch the top of my shoe).
I admit that I did not bleed the lines due to lack of knowlege on how to do it right. I siphoned some fluid out of the resoviour as I pushed in the pistons. When they were in far enough for the pads to clear the rotor, I stopped.
Any ideas?

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  #2  
Old 11-23-2004, 08:40 AM
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Hate to say it, but from what I've been hearing it probably needs a master cylinder. You could try a brake fluid flush first, has that been done recently? If you look at the mechanics of how a hydraulic brake system is supposed to work, the amount of wear on the pads doesn't really affect pedal travel, the pistons keep moving out to compensate for wear and the fluid in the reservoir take up the slack.
Gilly
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Old 11-23-2004, 07:40 PM
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flushed lately?

Yes, total brake fluid flush 15 months ago. I made an appointment at the dealer to check it out.
thanks.
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  #4  
Old 11-24-2004, 01:22 PM
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My break pedal travel has never changed and I flush the break fluid as specified. With new or worn pads I can't fill a difference. Still if I leave the other foot under the pedal, it will touch the top of my shoe.

Maybe there is nothing wrong with yours.

Rene
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  #5  
Old 11-24-2004, 02:13 PM
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Maybe nothing wrong..

But I can't remember if the pedal always went this low. I wouldn't say it just "touches" a shoe under the pedal, more like the pedal pushes down on a shoe underneath. It doesn't hit the floor though. Anyway, I'll have the tech's check it out next week.
Thanks.
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  #6  
Old 12-01-2004, 08:58 AM
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Problem solved?

Well, the dealer's tech's said nothing is wrong with the brakes. It still seems that the pedal is too low, but I'll see what happens over time.

Also, while in, got a new fuel pump installed due to occasional gauge problems. And, a new brake light switch due to the SRS/BAS light illuminating for no reason.

I think most of the vehicle has been replaced at this point.
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  #7  
Old 12-01-2004, 09:23 AM
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Nope, I bet the steering wheel and seats are all original. They really DO have to stop over-engineering the steering wheels and seats.........

Gilly
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  #8  
Old 12-01-2004, 10:54 AM
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Wink Everything replaced?

Well...actually the driver's seat heater is not working. But, you're right, the steering wheel seems to be allright!
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  #9  
Old 12-08-2004, 11:08 AM
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Master cylinder replaced

Well, the pedal just felt too low. It was really worrying me with a trip into the mountians in a few weeks. So, I went back to the dealer and they agreed that the next step is to replace the master cylinder. I hope this fixes it!
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  #10  
Old 12-09-2004, 02:05 PM
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brake problem fixed!

The master cylinder was replaced. Now the "grab" happens sooner and a foot can be under the brake pedal when fully depressed. Wow, I just knew it didn't feel right. Glad its back to normal.
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  #11  
Old 01-27-2005, 04:32 PM
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Just reading this because my brake pedal is beginning to feel the way ML320 Guy describes. So, if it's the master cylinder -

1 - how do I test for that problem?

2 - is it a DIY job?
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  #12  
Old 01-27-2005, 06:29 PM
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Diy?

Here's an update: while the pedal felt like it grabbed quicker after the repair, I do not have clearance under the pedal for another foot. So, I'm not sure the whole problem was fixed. As far as DIY, I do everything that I can myself. For instance, brake jobs are easy. But I don't know enough about bleeding the fluid, so I just keep the fluid at the right level. But, the master cylinder was out of my league.
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  #13  
Old 01-27-2005, 06:55 PM
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Master cylinders are usually easy to replace as long as the connections are accessable. Below is a diagram of the master cylinder for a 1999.
Attached Thumbnails
Brake pedal problem, gilly...-mastercyl.gif  
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  #14  
Old 01-27-2005, 07:04 PM
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Thanks guys;

So, any conclusion here on the trouble with what seems to be excessive brake pedal travel? Is there any other part(s), or wear, that causes this?

I'm really wondering how concerned I should be.
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  #15  
Old 01-27-2005, 07:26 PM
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Does the level of fluid in your reservior seem to be decreasing faster than normal? In other words do you think there is a leak but you can not account for where the brake fluid goes. The fluid can be sucked back into the brake diapharim, booster or whatever it's called so you will not see the leak.

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