CK your Calipers

[warren]

Note:

Over the last 2 years I have had 3 sets of performance brakes & rotors beyond the orig. ford ones for the front- Steering wheel just kept shaking.

Here is what I found ---

1st. set --- Rotors developed hot spots Blamed the mfg.--- Now I think the installer forgot to check the run out with a dial indicator---some installers just eyeball the rotor by just spinning it and you can't- must use the Dial Indicator to .003 runout at most ( runout is how much rotor moves side to side when turned while on car).

Got another set for the front and they went out as well -- It was metal pieces from edge of rotor getting cought in pads.

Got another set (this is the current set) --- Just had them checked by
brand new LessSchwabb center and low and behold --- the runout was
perfect >001, >002, .003, .002.
Pads looked great but one was worn more on one end- Rotors looked ok
(they are slotted with blind drilled holes)

I kept on thinking it was the mfg. It was not. But-- I did not watch the last 3 installations and now as the tech. pulled off the caliper it was evident that one piston was slower than the other on pass. side--- this was making the vibration problem and poor braking.

85K miles on the MM

Ordered New performance brakes and stainless steel braded brake lines.
The rotors will be turned on their on the car wheel lathe, slow cut, and ruffed up after for proper bedding.

Sooo CK your calipers!!!

Warren

[Stranger in the Black Sedan]

The rotors will be turned on their on the car wheel lathe, slow cut, and ruffed up after for proper bedding

I wish someone around here (trustworthy) did that, I'll have to look into it. I like on car turning because it factors in hub runout

How do you know that one piston retracting slower is the cause of your breaking problems? It may behave totally fine when you are actually braking with it. There aren't too many things that can go wrong with a caliper.

[burt ragio]

A lazy caliper will wrap rotor in a very short time.

[Taemian]

A lazy caliper will wrap rotor in a very short time.

+1. And so will overtorquing your lugnuts, I've seen it happen with cheapo rotors. Torque to spec, folks!

[warren]

Yes it's done -took 3 hours, new HP pads, turned rotors, installed SS brake lines and new calipers on 87K MM.

I watched as it was done and pass on these thoughts.

l. When you are on hand its hard for a mistake to be made.

2. Re-finished the old rotors using a on the wheel lathe ( slow speed ) on
the front hp rotors that are groved and blind drilled-now there is 0
runout.
Re-finished rear hp rotors on floor lathe as could only use on the
wheel lathe on the fronts.
Most of the places I called would not so these rotors or said it could
not be done. These folks do it all the time.
A Reverse Rake Bit must be used as the cutting head with a
negative rake instead of a positive one. Also they ruffed up surface
after turning with steelwool for better bedding.

3. Installed the new calipers as I mentioned on the 1st post and
the new ss brake lines. These ss lines needed 3 positive push
of bleeding & driving to get the brake pedal to feel solid.
They said that this is usually the case with ss lines to get out air
and stretch out the ss mesh. Told me to come back in 1000 miles
to make sure all was well.


Warren