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Replaced brake pads. All four corners brakes are locked up

  • Thread starter Thread starter Michael sommers
  • Start date Start date Sep 5, 2025
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Michael sommers

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Mar 25, 2020
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Springfield,MO
Sep 5, 2025
#1
  • Sep 5, 2025
  • #1
The car has 240k miles. The pads on both the front and back were extremely worn down.
After I replaced the front ones, they are completely locked up. I replaced the back ones, and with the car up in the air in drive it wants to die because they are dragging so bad. Is it possible I have 4 bad calipers?
 

Noobz347

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#2
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I think it more likely that you ended up with some fat pads or the calipers didn't get pushed down correctly.

I'm thinking we need a lot more info and probably some really good pics of what you have going on.

Part numbers for your replacement pads as well as good description of your install process would help too.
 

Michael sommers

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Sep 5, 2025
#3
  • Sep 5, 2025
  • #3
Noobz347 said:
I think it more likely that you ended up with some fat pads or the calipers didn't get pushed down correctly.

I'm thinking we need a lot more info and probably some really good pics of what you have going on.

Part numbers for your replacement pads as well as good description of your install process would help too.
Click to expand...
I had the special tool for the rears, it was pretty difficult to get them down. The front I had to use a c clamp and channel locks to twist the clamp hard enough to get one of the pistons down on each side. I lubed up the slide pins and they seemed to move freely. Brake pad part number for front is PD804M rear is PS627C
 

Noobz347

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They should all be the same in this section but... What year?

Did anything get galled up during the push and pry and twist efforts? Was the cap off of the M/C?

Did you try bleeding any of them?
 

Noobz347

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I'm going to move this [up] one forum since yours are the same as GT.

We'll get more eyes on it too.
 

Michael sommers

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#6
  • Sep 5, 2025
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Noobz347 said:
I'm going to move this [up] one forum since yours are the same as GT.

We'll get more eyes on it too.
Click to expand...
Noobz347 said:
They should all be the same in this section but... What year?

Did anything get galled up during the push and pry and twist efforts? Was the cap off of the M/C?

Did you try bleeding any of them?
Click to expand...
2003. I took the cap off while I compressed them. Visually, everything looks fine. I made sure and put lubricant in all the necessary places. I have not tried bleeding them
 

Noobz347

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#7
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Recommended diagnostic steps ​


After the car sits with engine off, crack a bleeder screw at one locked caliper.

- If fluid squirts under pressure and the wheel frees up → restriction is upstream (hose or master).
- If no change → caliper piston itself is stuck.


Check the brake pedal free play. If the pedal doesn’t return all the way, or if the pushrod into the master is too tight, residual pressure won’t bleed off.

Inspect rubber brake hoses for bulges, cracks, or stiffness. Replace if original — they’re cheap compared to calipers.

Verify the parking brake cables move freely when released.

Consider a full fluid flush/bleed. At 240k, the fluid is almost certainly overdue and may be part of the problem.


It’s almost never 4 bad calipers all at once. Much more likely you’re dealing with old hoses that are collapsing internally or a master cylinder issue holding residual pressure in the lines. The fact that all 4 are dragging points to a system-wide restriction. Try cracking a bleeder on a locked caliper: if it frees immediately, that confirms fluid is trapped upstream. At 240k, a set of new brake hoses and a full flush would be my first move before throwing calipers at it.
 

Michael sommers

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Mar 25, 2020
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Sep 5, 2025
#8
  • Sep 5, 2025
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Noobz347 said:

Recommended diagnostic steps ​


After the car sits with engine off, crack a bleeder screw at one locked caliper.

- If fluid squirts under pressure and the wheel frees up → restriction is upstream (hose or master).
- If no change → caliper piston itself is stuck.


Check the brake pedal free play. If the pedal doesn’t return all the way, or if the pushrod into the master is too tight, residual pressure won’t bleed off.

Inspect rubber brake hoses for bulges, cracks, or stiffness. Replace if original — they’re cheap compared to calipers.

Verify the parking brake cables move freely when released.

Consider a full fluid flush/bleed. At 240k, the fluid is almost certainly overdue and may be part of the problem.


It’s almost never 4 bad calipers all at once. Much more likely you’re dealing with old hoses that are collapsing internally or a master cylinder issue holding residual pressure in the lines. The fact that all 4 are dragging points to a system-wide restriction. Try cracking a bleeder on a locked caliper: if it frees immediately, that confirms fluid is trapped upstream. At 240k, a set of new brake hoses and a full flush would be my first move before throwing calipers at it.
Click to expand...
Well I cracked open a bleeder on one of the front ones, fluid trickled out but it is still completely locked up
 

Michael sommers

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Sep 5, 2025
#9
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Michael sommers said:
Well I cracked open a bleeder on one of the front ones, fluid trickled out but it is still completely locked up
Click to expand...
I will be replacing the lines/ flushing the system. Both front ones there was no change when I cracked it open. I will check the parking brake
 

stormsedge

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Michael sommers said:
2003. I took the cap off while I compressed them. Visually, everything looks fine. I made sure and put lubricant in all the necessary places. I have not tried bleeding them
Click to expand...
Did the fluid level rise in the master cylinder as you compressed the pistons?
 

Michael sommers

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stormsedge said:
Did the fluid level rise in the master cylinder as you compressed the pistons?
Click to expand...
Yes it did. It’s supposed to correct?
 
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Noobz347

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Yes
 
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stormsedge

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Michael sommers said:
Yes it did. It’s supposed to correct?
Click to expand...
Yes. At this point, @Noobz347 #7 is best advice. Happy Hunting.
 

Michael sommers

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#14
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stormsedge said:
Yes. At this point, @Noobz347 #7 is best advice. Happy Hunting.
Click to expand...
Well I’ve been messing with it lot, brake pedal returns nicely and has a good firm feel. Bled the brakes. Cracked open a bleeder and fluid would shoot out, but it did not free them up whatsoever. Parking brake is fully disengaged. I flushed the system and put new brake fluid in it. I’m not sure what to do at this point.
 

DadLife0724

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Sep 12, 2025
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I would think calipers. In my experience if you have to fight to get them to compress they are usually done. Does seem strange it happened on all 4 corners at once.
 
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Noobz347

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I think I may know what happened:

The front brakes are [push] in. Clamp, vice, etc...

The rear brakes are supposed to be [screw] in as you apply pressure.


So, I think you may have destroyed the rears.

It's also possible that you need all new soft lines. Pickup banjo bolts and washer too, if they don't come with.
 
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DadLife0724

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#17
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I just had hoses on my excursion collapse and turn into one way valves.

Yikes on those rears. Hopefully that's not the case. I'm rootin for ya.
 
Last edited: Sep 12, 2025
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Michael sommers

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Sep 12, 2025
#18
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Noobz347 said:
I think I may know what happened:

The front brakes are [push] in. Clamp, vice, etc...

The rear brakes are supposed to be [screw] in as you apply pressure.


So, I think you may have destroyed the rears.

It's also possible that you need all new soft lines. Pickup banjo bolts and washer too, if they don't come with.
Click to expand...
I had the proper tool for the rears that fits in the slots on the piston and twist while it pushes it in. Going to be replacing the soft lines. Just to test I put the old pads back in one of the front calipers, it spins but even then it seems to drag quite a bit, and these pads are VERY worn down.
 
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gkomo

now i can hopefully expect to receive the shaft
Aug 2, 2024
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Is it normal for fluid to ‘shoot out’ when the bleeder is cracked or should it just flow out? Can the system have too much pressure somehow?
 

Noobz347

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gkomo said:
Is it normal for fluid to ‘shoot out’ when the bleeder is cracked or should it just flow out? Can the system have too much pressure somehow?
Click to expand...

No. It should not come [shooting] out unless it's trapped somehow.

Trying to figure out exactly where it is trapped, over the interwebz can be a challenge. lol
 
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