Brake question

[cycleguy55]

Originally Posted by Tom Wells

classical,

Maybe you took care of this, maybe not?

Your car's rotors may have a layer called "glaze" due to deposition of the prior pad material. If this isn't removed by a light turning or maybe some emery cloth, you may find the car won't stop well no matter how high the braking line pressure.

A layer of glaze definitely has a lower coefficient of friction.

I'd suggest looking at this before trying other sized cylinders.

Just another possibility...

Tom

PS: It looks like the front rotors were turned? If so, you could still check the rears. If they're OK then maybe do what Bob proposed.

The front brake rotors on my wife's car (Infiniti G35x) were worn beyond specification, so I ordered a 'Power Stop' brake kit from Rock Auto. It's nothing fancy or high performance, just OEM equivalent - Infiniti generally equipped them with decent brakes, so I didn't think I needed to go high end.

I installed the kit and went through the whole break-in procedure:

Break in the pads as follows: 5 moderate to aggressive stops at 40 mph to 5 mph without letting the brakes cool and do not come to a complete stop. Then do 5 moderate stops at 25 mph to 5 mph and let the rotors cool after each brake application. You should expect to smell some resin as the brakes get hot.

We live in a bedroom community of about 6,000 and we're only about a mile from a quiet, two lane rural highway. Perfect for breaking in a new set of brakes, right? I followed the above instructions carefully to ensure it was done right. Did I smell some resin? You bet! Did I have smoke coming out of the wheel wells? Not billowing clouds, but it was there.

I thought that car stopped pretty well before - but what a world of difference. After that I took my Infiniti FX35 through a similar procedure - the gains weren't as dramatic, but they were there.

Moral of the story - proper break-in makes a world of difference. Even repeating it with old rotors and pads can help - I imagine more improvement if they're glazed.

BTW, I'd also recommend cleaning the rotors with brake cleaner before the break-in procedure, even with old rotors and pads. It might not be a bad idea to take some sandpaper or a grinder to the old pads to knock off any glaze you find.