Fix for under-boosted brakes? [Archive] - Glock Talk

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Tennessee Slim
06-08-2008, 19:28
Last week I picked up a 2001 Outback and Iím in the process of freshening it up a bit. I took it to a trusted import repair shop to have it checked out, especially the brakes. The pedal effort seems unusually high but they still have enough power to activate the ABS. The mechanic agreed that the pedal effort was high but couldnít find anything out of whack with the braking system.

This is my first Subie but Iím guessing the high brake effort isnít normal. I suppose, in time, I could adapt but Iíd sooner adapt the brakes to me.

So where would you start? The pads and rotors are okay but Iím not opposed to replacing/upgrading them on general principle. The hoses appear in good shape and my mechanic thinks the master cylinder is okay.

If it were your car, where would you start?

AutomotiveTech
06-09-2008, 09:52
I would check the vacuum to the brake booster, and that the diaphram in the booster is not leaking. If the booster is leaking vacuum internally you should hear a hissing noise, sometimes when you hit the brakes and sometimes when your foot is off the brake depending on the failure.

Ron3
06-09-2008, 16:36
It's probobly just you and the pedel effort is normal but more than you prefer.

Or you could really have a problem.

Are the pads new? Are the rotors bright and shiny? (Glazed) If so, machining the rotors and ensuring the pads are bed in properly will help.

To bed in pads start with a fresh surface on the pads and rotors, then go out and stop the brakes until they fade a little and stink. Then drive easy so the brakes can cool down or park the car while. (Leave your parking brake off)

Most organic type pads will bed in with several hundred miles of normal driving and braking if you don't want to go through the extra effort.

After market "ceramic" and "semi-metallic" pads with long warranties often come with high effort, poor cold performance, and noise.

Make sure you don't have any twisted brake hoses too!

Hope something here helps.

Ron3

Tennessee Slim
06-11-2008, 09:05
I can't hear any hissing, plus I already had mechanics I trust checking it out. Since I mentioned the brakes specifically to them, I'm confident they did better job checking it out than I can.

I was thinking glazing myself but it'll be a week or two before I work up the gumption to change them out (the mechanics are asking too much).

Ron3
06-11-2008, 20:35
I can't hear any hissing, plus I already had mechanics I trust checking it out. Since I mentioned the brakes specifically to them, I'm confident they did better job checking it out than I can.

I was thinking glazing myself but it'll be a week or two before I work up the gumption to change them out (the mechanics are asking too much).

You can scuff the pads up on pavement and have the rotors machined.

Then you can bed them in properly.

Ron3