Brake Question

[CiK]

I have a 2008 F150 I am changing the front pads and rotors on. I have a question about brakes in general. How much travel should front pads have before they hit the rotors? Or, are they always in constant contact?

Thanks guys!

[JerryT]

They dont generally touch when not applied...But you wont be able to tell

[aussiebasser]

You can't adjust the clearance. It's all automagic in the calipers. Dunno how it works, but just glad it does.

[CiK]

<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by JerryT &raquo;</td></tr><tr><td class="quote"> They dont generally touch when not applied...But you wont be able to tell</td></tr></table>

Won't be able to tell as in "its not a bad thing if they are" or won't be able to tell as in "the distance traveled is so small its negligible".

I am worried if they are touching about too much heat.

[TNT]

<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by aussiebasser &raquo;</td></tr><tr><td class="quote"> Dunno how it works, but just glad it does.</td></tr></table>

Hey! How exactly is a rainbow made? How exactly does a sun set? How exactly does a posi-trac rear-end on a Plymouth work? It just does.

[overspray]

The pads are always touching ......its not much, just a light rubbing, but they do touch.

[mkmsports41]

Your rotors will generally always be in "slight" contact with the pads. The calipers have a piston in them. On the piston is a square cut o-ring. Behind the o-ring is brake fluid. Your brake pedal is a pump. When you hit the pedal the fluid pushes the caliper piston out against the pad. The pad then touches the rotor. Once you let off the pedal and the vehicle moves the turning of the rotor will allow the piston to come back. Also by letting off of the pedal you will creat a small about of "vacumm" that will suck the caliper piston back as well.

The easiest way to tell if you need brakes is by looking at your brake fluid reservoir. If the fluid is below the full mark that tells you that the pistons are out farther meaning your pads are wore. Now this wont tell if its front or rear but its a good thing to look at when checking the oil.

[mkmsports41]

<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by TNT &raquo;</td></tr><tr><td class="quote">

Hey! How exactly is a rainbow made? How exactly does a sun set? How exactly does a posi-trac rear-end on a Plymouth work? It just does.
</td></tr></table>

JOE DIRT JOE DIRT JOE DIRT

[CiK]

Thanks guys! Last question. If they are always touching then they will create heat. How much heat though? Warm to the touch or hot to the touch after driving?

[Cyncwby]

They touch or barely skim the rotor...that's how they are engineered, they are always hot because of the ambient temps from the wheel bearings, tires etc.....don't worry about it.

[overspray]

They do get hot from driving and braking. Next time you stop and get out of the vehicle, walk up to them and touch them. I wouldn't hold your fingers on them for very long because they will burn your finger.

[CiK]

Sweet! From your replies I have come to the conclusion I did it right. I took it out after done and touched the rotor through the wheel and wished I hadn't.

This was my first time do it yourself'er brake job. If any of you in the Cincinnati area see me on the morning news then something went wrong.

Thanks guys!

[overspray]

<table width="90%" cellspacing=0 cellpadding=0 align=center><tr><td>Quote, originally posted by CiK &raquo;</td></tr><tr><td class="quote">

This was my first time do it yourself'er brake job. If any of you in the Cincinnati area see me on the morning news then something went wrong.

Thanks guys!</td></tr></table>

I live a little farther north of you.....but I'll keep an eye out.

[Jeff Hahn]

Yes, they touch. But, as long as your rims are not too hot to touch, the brakes are fine. But, the rotors will be too hot to ouch, even when the brakes are working fine. Don't ask me how I know.

[Walkabout7781]

While I was going to college, I had a PT job at a tire store. Somebody brought in a car that a local gas station/garage had done a brake job on. The 'mechanic' had put in the front brake pads (discs) backwards, so metal on metal, instead of friction material on metal. The tire store got paid and the gas station paid the bill.

It is possible to screw it up. Drums are trickier, with leading shoe and trailing shoe and all that. I always worked on one side at a time, so I could go 'round and look at the other side if I had any doubts at all.

One thing that you might do wrong when putting in new shoes and/or pads, is that your brake fluid level could be too high and spill over. Typical DOT 3 brake fluid will eat paint in a flash. The Silicon DOT 4 brake fluid does not, and I use it in my boat trailer and used it in my '68 GMC hotrod truck with 4w discs. Flushing the brake system is time and money well spent, too.