New Pads = no stop???

[jeeperjohn]

Did you lube/replace the caliper pins? The pins can get gunked up with old grease and prevent the caliper from sliding properly and cause less contact of the brake pads on the rotors. If this is not the problem then the only thing that fits the symptoms you described is air in the system somewhere. It shouldn't have been able to get air in just by pushing the pistons back in but the symptoms point to that.

 

[QuillsXJ]

His problem is a soft pedal that offers very little resistance when pushing on the brakes. Pad and surface of pad quality is irrelevant here. Your problem is in your brake booster/hydraulic system. Look for leaks on the inside of your tires, monitor your master cylinder fluid level for a week or so. A good test of your booster system is about 4-6 pumps on the pedal when the ignition is off. The pedal should rise after each pump until finally it becomes extremely hard. Then start the car and it should drop to normal operation. If this system is functioning well then you have hydraulic leaks, induced air in the system, etc.

 

[keep0njeepin0n]

Did you change to ceramic or some other hi-perf. type of pad? Some of them need a lot of pressure to work properly but they won't fade or wear out in serious use.

I found that out about mine too. I noticed a really big difference when I switched to ceramic pads. Switched back to semi-metallics (same brand) and everything is great now!

Did you lube/replace the caliper pins? The pins can get gunked up with old grease and prevent the caliper from sliding properly and cause less contact of the brake pads on the rotors. If this is not the problem then the only thing that fits the symptoms you described is air in the system somewhere. It shouldn't have been able to get air in just by pushing the pistons back in but the symptoms point to that.

His XJ doesn't have caliper pins, but it does have slides on top and bottom that should be cleaned/lubed. You're right though, air did not get into the system just by pushing back the pistons, unless he has a leak, which I'd be willing to bet he doesn't since he didn't have this problem until AFTER the brake job. I see this all the time, people want to mis-diagnose something....things just don't go bad like that especially when the vehicle was driven right before and right after. Now if he said a month after the brake job, then ok, let's look at other things.

Anyway, I would start by checking to make sure you used the correct type of pad AND also check to make sure the pads are seated, both in the caliper piston where it pushes in and clips in place, AND on the outboard pad where it clips onto the outside of the caliper itself. We had this same problem at my work on a Ford Escape and after bleeding the brakes 3 times, we found that the tech had gotten in a hurry and didn't have one of the pads seated properly.

 

[Djmack]

His problem is a soft pedal that offers very little resistance when pushing on the brakes. Pad and surface of pad quality is irrelevant here. Your problem is in your brake booster/hydraulic system. Look for leaks on the inside of your tires, monitor your master cylinder fluid level for a week or so. A good test of your booster system is about 4-6 pumps on the pedal when the ignition is off. The pedal should rise after each pump until finally it becomes extremely hard. Then start the car and it should drop to normal operation. If this system is functioning well then you have hydraulic leaks, induced air in the system, etc.

from all the information ive read... this is the most likely of all the scenarios listed.

go ahead and replace it, if its not the problem, then you at least know that you have another thing off the list.

 

[JJacobs]

from all the information ive read... this is the most likely of all the scenarios listed.

go ahead and replace it, if its not the problem, then you at least know that you have another thing off the list.

Parts stores love that approach. It's good for the economy. Keep replacing stuff and you'll eventually get it- and the Jeep will be like new!

 

[89xj]

No other parts were replaced, pads only. i did the job my self. bedded with 8, 50mph to 10mph hard stops then drove and let cool for 20min still not much behind pedal. will stop (slowley) but not near as well as the last cheepy pads.

cheapy pads work well but wear fast, what pads did you install?

did you check for glazing after the break in?

 

[J-Roc]

Parts stores love that approach. It's good for the economy. Keep replacing stuff and you'll eventually get it- and the Jeep will be like new!

Actually we hate it, because the cheap bastard that bought all the cheap replacement stuff tries to take back the stuff that "didn't fix his problem" :explosion

 

[CMAHON]

INSTALLED DURALAST C-MAX. no leakes anywhere. not sure what glazing is though. will get pressure after a couple pumps w/ engine off.

 

[CMAHON]

is it possible to install on wrong side (driver vs. pass) and could this cause said effects?

 

[QuillsXJ]

Left to right doesn't matter as there are two sets of the same pair of pads per wheel. There is a top and a bottom to a pad and one pad matches to another pad to make a pair per wheel and they are directional, just a few things to consider when installing. If your brake booster is functioning properly and you have no leaks I am at a loss for why your pedal has little resistance. Maybe air in the system? Do you think that because you installed new pads and are in the brake in period and it's taking more effort to stop that you are wrong about your pedal and it's functioning the exact same as it was before?

 

[PhotographerMike]

Did a bit of checking;

From AutoZone web site; "Notes: Friction: Maximum ceramic formulation
Friction Material Type: Ceramic"

From Tire Rack web site;
http://www.tirerack.com/brakes/resu...l=Cherokee+Classic&autoYear=1999&autoModClar=
Note that the Ceramic pads have the lowest "Stopping power" ratings.

"Best" or most expensive might not be the best for everyday use. Ceramic might be great on the track with a completely upgraded brake system that is always well warmed up, but for daily use there can be drawbacks.

 

[CMAHON]

Left to right doesn't matter as there are two sets of the same pair of pads per wheel. There is a top and a bottom to a pad and one pad matches to another pad to make a pair per wheel and they are directional, just a few things to consider when installing. If your brake booster is functioning properly and you have no leaks I am at a loss for why your pedal has little resistance. Maybe air in the system? Do you think that because you installed new pads and are in the brake in period and it's taking more effort to stop that you are wrong about your pedal and it's functioning the exact same as it was before?

there is definitly a difference. but after said that i have never ran ceramic pads before so i am unfamilier with them. that may be working the way they should i just have nothing to compair to except my old ones. but i will be checking (or bleeding) this weekend.

 

[CMAHON]

Did a bit of checking;

From AutoZone web site; "Notes: Friction: Maximum ceramic formulation
Friction Material Type: Ceramic"

From Tire Rack web site;
http://www.tirerack.com/brakes/resu...l=Cherokee+Classic&autoYear=1999&autoModClar=
Note that the Ceramic pads have the lowest "Stopping power" ratings.

"Best" or most expensive might not be the best for everyday use. Ceramic might be great on the track with a completely upgraded brake system that is always well warmed up, but for daily use there can be drawbacks.

when i inquired about the pads i specificaly wanted best stoping power. that is what was recomended to me. maybe i just got sold?

 

[PhotographerMike]

And you probably got the "best stopping power" from what the sales person knew or was told, just not the best for your use.
It always bothers me when sales people (and I might be one myself at times) don't first ask what the end use will be and recommend from there.
What works for a ricer racer might not work at 10 mph in dirt and vice versa.

 

[89xj]

did you check to make sure the rear drums are adjusted proporly?

the auto adjusters dont always work and i have always felt that adjusting them manually works much better. did you check the coondition of the rear shoes and drums, sometimes this gets overlooked when replacing the front discs.

 

[keep0njeepin0n]

I say replace the C-MAX with a good semi-metallic from Carquest...Napa also has some really nice brakes at a good price!


Edit: I use carquest pads on a DAILY basis at work and I warranty MAYBE 1-2 sets a year....same with NAPA pads! As far as AZ pads....I don't run them unless I have to.