Help! Brake pads not making full contact with rotor!

[Tickle]

I installed new pads rotors over the weekend, all four corners.

After driving it around, I noticed that the PS front isn't marking the rotor with the full width of the pad compared to the DS front.

Before I take the front brakes apart again, I was hoping to get some advice.

DS Front(Looks good):

PS Front:

What should I look at first? My thoughts were that something isnt seated properly. I thought I double checked everything. Did I mix up a pad?

I installed Hawk HPS pads and rotorpros drilled/slotted rotors.

 

[SublimeRT]

Press the brake pedal harder. :lol1:




But no, seriously. A few different things I can think of off the top of my head; trash between the rotor and hub, sticking/damaged piston(s) in the caliper, loose caliper, trash between the caliper and mounting bracket, wrong pads for the car, incorrectly installed pads, I've even come across a kinked brake hose before from I guess where someone took off the caliper and unknowingly spun it around, pinching off most of the fluid flow. I would suggest you pull the wheels off and thoroughly inspect everything again. How does it drive? Pull to one side under braking? Any vibrations? Any noises or clunks? How many miles have you put on it since installing them? How did the wear patterns on the old rotors and pads look? Could tell a story.

 

[SublimeRT]

I just saw this post of yours.

http://www.svtperformance.com/forums/sn95-cobras-24/950730-rusted-seized-brake-rotors-suck.html

Did you use this method with the fronts and bend something???

Did you clean the rust off the hub thoroughly after removing the rotor?

For future reference, I've never come across a rotor I couldn't remove without squirting some penetrating oil through the wheel stud holes, letting it do it's work, and hitting the face of the rotor, the wheel mounting surface, with a mini sledge. Takes a few whacks and you can't be shy about it and watch out for the studs, wrap them with something if you must, but it's always worked for me.

 

[SublimeRT]

I just saw this too.

http://www.svtperformance.com/forums/sn95-cobras-24/949327-vibration-55-70mph.html

What fixed the vibe? Anything yet? The fact you say you can feel the vibe in the steering wheel raises an eyebrow. I see front hubs were installed. Were they torqued correctly? I'm just thinking out loud here.

 

[Tickle]

Press the brake pedal harder. :lol1:

How does it drive? Pull to one side under braking? Any vibrations? Any noises or clunks? How many miles have you put on it since installing them? How did the wear patterns on the old rotors and pads look? Could tell a story.

I'll take them apart and inspect them tonight. It drives fine, no vibrations, no pulling, didn't see any uneven wear previously. I'll inspect further on the old stuff also. I have driven 30 miles or so.

 

[Tickle]

I just saw this post of yours.

http://www.svtperformance.com/forums/sn95-cobras-24/950730-rusted-seized-brake-rotors-suck.html

Did you use this method with the fronts and bend something???

Did you clean the rust off the hub thoroughly after removing the rotor?

For future reference, I've never come across a rotor I couldn't remove without squirting some penetrating oil through the wheel stud holes, letting it do it's work, and hitting the face of the rotor, the wheel mounting surface, with a mini sledge. Takes a few whacks and you can't be shy about it and watch out for the studs, wrap them with something if you must, but it's always worked for me.

I didn't have to use anything to remove the front, I fought that battle when I changed front hubs, sledgehammer eventually separated the old hub and rotor then, no bolts used to pop them off.

 

[Tickle]

I just saw this too.

http://www.svtperformance.com/forums/sn95-cobras-24/949327-vibration-55-70mph.html

What fixed the vibe? Anything yet? The fact you say you can feel the vibe in the steering wheel raises an eyebrow. I see front hubs were installed. Were they torqued correctly? I'm just thinking out loud here.

No, haven't fixed it yet ---havent had time to get it to a tire shop to inspect further.

Hubs were torqued to spec(iirc it was a TON of torque)

Vibration occurred before and after hub installation.

Thanks for your help on this, that's a lot of connecting the dots on other threads..much appreciated.

 

[Tickle]

Took it apart and nothing looked bad, inspected old parts and there's no evidence that this was happening before.i did verify that the pads aren't fully contacting on both sides.

Test drive it again and it stops great. Smooth, good feel, no vibration or noise, no pulling. Still no full marks from the pads.

I guess it's gotta be the caliper?

I don't have much time in the near future to do much, may just take it to a brake shop and have them take a look.

This is Frustrating.

 

[SublimeRT]

It does sound frustrating. I hate throwing parts at a car in an attempt to fix something; it's a good way to waste a lot of money, and it's sometimes difficult to diagnose a car without seeing it. So I'm not going to tell you it is in fact a caliper.

If you are 100% sure everything is torqued to spec (even the wheels, over torquing them can warp rotors) and everything is in alignment and not bent and nothing else is obviously wrong and you do not have incorrect parts, I would probably try to have a look at the caliper while someone is pressing the brake pedal. You could do this without removing the wheel and see if anything is moving under pressure. Maybe something is cracked and you can't see it when it's not stressed? Maybe remove the wheels, rotors, and pads and do the same test while someone eases on the pedal to see what the pistons are doing and if you can push them back in without too much drama. Definitely not the same stresses as on the car and in motion but it might give a clue. You could remove the wheel, reinstall a few lug nuts and lightly snug them down, just enough so the rotor doesn't move off the hub, and measure run out of the rotor with a dial indicator, and play in the hub too while you're at it. Did you do any bleeding of the brakes? How does the fluid look? Maybe there is some air in the system somewhere? Trash in the system or in a distribution block? Valve in the ABS block stuck?

Some of these suggestions are probably a bit off base or extreme, but when chasing down a problem you have to consider everything and can't even rule out a part just because it's new. Obviously though, start with the simple stuff. I'd be looking at the caliper. If you are comfortable with it, rebuild kits for calipers are usually pretty cheap. If there is nothing wrong with the caliper body, piston bores, or pistons (the pistons could be replaced if something was wrong with one though) rebuilding them is just as good of an option as replacing them. Good chance to paint them up nicely as well. If they're original calipers and they haven't been rebuilt that very well could be the problem, these cars are creeping up on twenty years old after all. Maybe someone else will chime in, I know there are some pretty sharp guys on here.

 

[Slow95Cobra]

Anti rattle clips installed and lubed? Did you put new rotors on? Check the old pad for a slight taper, you can also get a micrometer and check rotor thickness close to hub and outer edge to see if the rotor is outta shape

 

[CJK440]

Swap the pads drivers to pass and see if it follows.

 

[Jonesy98]

sounds to me bad caliper, or the shoulder of the guide pin is resting up against the caliper housing?

 

[Tickle]

sounds to me bad caliper, or the shoulder of the guide pin is resting up against the caliper housing?

I'm pretty sure this was it. I'm now seeing full pad marks on the rotor on the outside. Gonna check the inside when I get home tonight.

 

[Goindeafonmtx]

When you jam on the brakes, does it pull to one direction?

 

[Tickle]

When you jam on the brakes, does it pull to one direction?

It's hasn't yet, but it did seen to pull a little on the way him from work which might have been the road causing my steering to track