Breaks are sluggish

[thorschanck]

My wife drives our 03 liberty limited. Recently I drove it and noticed that the breaks are very sluggish. I replaced the frog pads today and noticed that the old pads weren't even in bad shape at all. The breaks do not function any different after the pad change. If I am driving and stomp the break pedal to the ground the car comes to a very slow stop. It is impossible to get the breaks to react quickly. Also when I put the new pads on it was nearly impossible to get the calipers on over them. Even after I pushed the piston all the way in. I checked the pads and they are the proper ones for the car. I'm really puzzled with this one. The caliper doesn't seem to be leaking or anything it almost just seems as if there is somethin restricting the flow of fluid in the break lines.

 

[JeepJeepster]

Piston easily press back in?

Sliders easily slide? Mine was doing that when all of my sliders seized up after using permatex brake grease made for sliders but made the rubber swell. Junk that stuff is

 

[tommudd]

Did you replace the rotors as well? If not the rotors get a glaze on them and that a affects the performance of the brakes
Also the things Jeepster mentioned, plus always should install new hardware when doing a brake job.
So,
calipers( pistons) could be sticking
hardware dirty/corroded/sticking
calipers glazed over
rubber lines could be collapsing

Just throwing a set of pads on without replacing the rotors and hardware is like buying new shoes and still having holey socks on

 

[thorschanck]

Put new hardware on with the shoes. The piston pushed in easily. And the rotors aren't more than a few years old. Could it be air in the break lines? Don't know how that could happen but might I need to bleed the lines?

 

[uss2defiant]

okay. I have no expertise in this area but

maybe the caliper is stuck?
The rods might need a look through and it might be binding up?
Might need to clean and relube them w/ silicon based lube.

Maybe there's air in the system?
You might need to bleed it.

I think new pads need to break in?
But I think you need to turn your rotor to removed the old material left by your old brake pads. Either that or replace the rotor.


Ditto on what everyone else is saying.

 

[dude1116]

Did you grease the slides? Also did you grease the tabs on the brake pads? Maybe the pads aren't pulled all the way off the rotor.

Also a rotor a few years old could easily need replacing. Depending on brand, driving habits and conditions, etc.

Also you referred to shoes. You have an '03 which has 4 wheel disc and pads. No shoes.

 

[CactusJacked]

And the rotors aren't more than a few years old.

Did you replace the rotors as well? If not the rotors get a glaze on them and that a affects the performance of the brakes

This is the first thing that came to my mind. Doesn't matter that the rotors are only a few years old. They have a (slick surface) glaze on them, and with new pads you want to dress down (sand) the old rotors till the shine is gone. Otherwise, the new pads won't break-in with the rotors, and will not grab as they should. Take care of that first before assuming you have other problems.

 

[thorschanck]

My apologies I mistyped on the shoes. I know they are pads. I greased everything up maybe I will try turning the rotors. Also when I put the calipers back on they were really tight on the pads. It honestly doesn't seem like an issue of the pads not gripping the shoes it seems more like an issue ofte pads not getting any pressure on the shoes.

 

[uss2defiant]

keep us posted.

 

[tjkj2002]

The most over looked possibility,bad brake fluid.The use of aluminum parts in the braking system breaks down the fluid much faster these days and should be flushed every 2-3 years,1-2 years if you have ABS.




I have improved brake feel by just doing a simple brake flush on many vehicles,not bleeding the brakes just flushing the fluid out with new.

 

[agb0244]

I haven't read far enough yet, but it sounds like power brake booster to me

 

[agb0244]

Check the vacuum off the intake that goes to the brake booster. No vacuum no brake booster

 

[the_dealer]

With the engine at idle pump the pedal a few times til it gets hard. Immediately shut the Jeep off. Wait about 15 minutes, then with the jeep still off, see if the pedal is still hard.

Does the pedal slowly sink to the floor when u are stopped? I agree with tjkj2002, a simple brake fluid flush greatly improves braking performance

 

[tjkj2002]

With the engine at idle pump the pedal a few times til it gets hard. Immediately shut the Jeep off. Wait about 15 minutes, then with the jeep still off, see if the pedal is still hard.

Does the pedal slowly sink to the floor when u are stopped? I agree with tjkj2002, a simple brake fluid flush greatly improves braking performance

With engine off pump the brake pedal till it get's hard,put moderate pressure on brake pedal and start the engine.The pedal should fall(keep steady pressure on it) a few inches(2-3 is okay depending on vehicle).If it does not drop you have a vacuum issue or bad booster,if the pedal keeps falling you have a bad master.




Pumping the pedal with the engine running will do nothing to help diagnose the brake system besides reveal leaks.

 

[the_dealer]

You're right tjkj2002, I got it twisted. It was one of those days, I dunno what the hell I was trying to get him to do.

I would be stopped in traffic and my pedal would slowly fall to the floor. I had a few other issues besides the mc, so I did powerstop rotors/pads, mc, and calipers.