Silverado Front Brakes Locking Up

[Pkpk231]

I have a 2007 Z71 4WD Silverado. Front brakes randomly lock up. Starts with a slow rub, I can feel the truck not accelerating like it should, and brake pedal stiffens a little. After a mile of driving 65 mph, 2-3 miles if I'm going 25-35 mph... Brakes completely lockup, truck won't move at all. Once it locks up completely, brake pedal is very stiff, takes a lot to depress it. Front wheels get really hot, back wheels feel normal. Brakes will break free after letting the truck sit for about 2 hours, and works fine after.

 

This happens sporadically, once every 2 weeks or so. Cant figure out what triggers it, happens driving down highway, back roads, wherever. Had the calipers, pads and brake fluid replaced 4 months ago. It was happening before then, so that didn't fix it.

 

Any thoughts on what might be causing this? Thanks in advance for any replies.

[anumber1]

The rubber, flexible brake hose attached to the caliper may be deteriorating internally. The hose will not allow brake fluid back out of the caliper when you let off the pedal.

 

As the dragging caliper heats up, the pressure builds. Also, with every stop, the pressure also increases. Eventually, as you have experienced, the brake completely locks up.

 

The master cylinder may also be the culprit but I would personally start by replacing the hoses.

[Long Box 2k]

Al is correct.

[Dnt]

Yes I second that motion replace the rubber flex lines. Very common issue.

[CapitalTruck]

As was mentioned, the only other thing would be slow vacuum leak in master cylinder which gradually applies the brakes.

[jrow8162]

Check your brake booster for brake fluid. Had the same issue with mine. Fluid leaked from the master into the booster causing the brakes to start to engage by themselves. New Master Cylinder and new Booster fixed the problem for me.

[Jesse sanchez]

Front hoses on both side have been replaced, so have calipers and abs. As well as the hub Barron’s . Still having the brakes locking up. Don’t know what else to replace??? Help!!!!

[rjgti]

master then

[Mike GMC]

Do you have vacuum boost or hydro boost master?

[davester]

yeah, if your truck has the hydroboost setup, you might consider flushing the power steering system so it has new fluid.

[Blknyellow517]

Jesse, did you figure anything out? I have a 06 I have been battling with for almost a year now on these brakes, I have replaced everything but actual lines, I have brand new calipers, pads, rotors, master cylinder, brake booster, rubber lines on both fronts, lasted a couple months and just the other day she locked up and now doing it all over again! I’m lost

 

truck does it a lot again, about 10 minutes of driving you can feel the brakes start to drag, what I did to unlock brakes was cracked bleeder on driver caliper, after doing that it’s fine for another day almost! 
 

here’s another one, on my way home from work, felt it start to drag, so I started wobbling steering wheel back and forward quickly and slightly, nothing making truck shake, but it made the dragging go away…. I’m telling y’all I am lost, I need help

Edited June 24, 2021 by Blknyellow517

[Paul McDonald]

Having the same issue with an 06.

Please update here if you find the fix

[Jimbosays]

On 6/22/2021 at 6:48 PM, Blknyellow517 said:

Jesse, did you figure anything out? I have a 06 I have been battling with for almost a year now on these brakes, I have replaced everything but actual lines, I have brand new calipers, pads, rotors, master cylinder, brake booster, rubber lines on both fronts, lasted a couple months and just the other day she locked up and now doing it all over again! I’m lost

 

truck does it a lot again, about 10 minutes of driving you can feel the brakes start to drag, what I did to unlock brakes was cracked bleeder on driver caliper, after doing that it’s fine for another day almost! 
 

here’s another one, on my way home from work, felt it start to drag, so I started wobbling steering wheel back and forward quickly and slightly, nothing making truck shake, but it made the dragging go away…. I’m telling y’all I am lost, I need help

Like this shared post, I have done ALL of the above with the same results

Has anyone found a legitimate solution for the well documented front brake issue??? 

*2006 GMC SLT, Crew Cab, 5.3L

[swathdiver]

On 7/28/2023 at 2:09 PM, Jimbosays said:

Like this shared post, I have done ALL of the above with the same results

Has anyone found a legitimate solution for the well documented front brake issue??? 

*2006 GMC SLT, Crew Cab, 5.3L

Did you not replace the brake lines Jimbo?  They can collapse internally.