Breaks acting up funny?

[tybcr783]

Hey yall, I got my 2000 Chevy C2500 ( 8 lug ), and her brakes act up only after it rains and at low speeds. Its been happening for a couple months now, I'd get out of school and slowly maneuver around the parking lot and with a little bit of break pressure it feels like my breaks seize up and the truck just lurches forward, I believe its my front drivers side tire that skids. Asked my father and he suspects a warped rotor. The breaks were fully serviced about 9 months ago so I wanted to see if anyone has had a similar experience. Thanks

 

[tybcr783]

Sorry for the improper grammar at the title.

 

[Pinger]

Mine are grabby when cold (and possibly wet) to the point of activating ABS on tarmac at slow speed. Winter here (so winter cold). Once past that, fine for the rest of the day. New rotors not that long back. Bosch ceramic pads. Never had brakes behave so grabbily when cold before but as they come good pretty quickly, I'm not losing sleep over them.
NB. Also a 8 lug C2500.

 

[Nad_Yvalhosert]

Same here with my 8-lug rear brakes. My current 1995 C2500 & my former 1998 K2500 Suburban. Both would roll freely, but lock up to a skid at slow speeds, at the end of my driveway, first thing in the morning when the temp was low.

I suspect high brake temps (compared to ambient temp) inside the drums from the previous day, and a large surface contact area, caused winter "condensation" to form inside my brakes, and/or form rust on the brake drums overnight.

Yeah, it is irritating, but it only happens the first time I hit the brakes. Then it goes away until tomorrow.

 

[Road Trip]

Hey yall, I got my 2000 Chevy C2500 ( 8 lug ), and her brakes act up only after it rains and at low speeds. Its been happening for a couple months now, I'd get out of school and slowly maneuver around the parking lot and with a little bit of break pressure it feels like my breaks seize up and the truck just lurches forward, I believe its my front drivers side tire that skids. Asked my father and he suspects a warped rotor. The breaks were fully serviced about 9 months ago so I wanted to see if anyone has had a similar experience. Thanks

I have a '99 C2500 8-lugger w/JD7 brakes, and after the first couple of stops of the day the brakes are
always absolutely smooth & confidence-inspiring. (This is with recently refreshed rear drums and unknown vintage
front rotors, pads, & calipers from the PO.)

Given this, I do not suspect any front rotor warpage. So smooth that I haven't had any inclination
to measure the runout?

On the other hand, if the truck isn't driven every single day, I do seem to feel something similar to
what you described on the first stop or two. Curiousity piqued, I performed a close visual inspection
of the front rotors prior to driving it one time, and noticed a bit of 'flash rust' on the rotor's friction
faces? But only where the rotor was exposed to the air, for if you moved the truck ~1/2 a tire revolution
you could see that the rotor surface that was underneath the brake pads was still shiny, *not* rusted?

And it seemed that the 'flash rusted' area was indeed more grabby/nonlinear than the smoother unrusted spot.
If you braked at low speeds you could feel the difference as a 'pulsation', not in the pedal, but as how the
whole truck was slowing down. But once the rotors were made uniformly shiny again by the pads (usually
by the end of the 2nd stop) ...all was well, so I haven't pursued any kind of remedy...if one is even possible,
given how much raw rotor surface is exposed to the elements.

And I am confident we're experiencing similar symptoms, for the problem is absent during a dry spell, but almost
always shows up when it's rainy/humid out.

Then again, on my vehicle the problem has never gotten any worse. But if this symptom is worsening over time
on your truck, this means that some mechanical relationship is changing over time? It's perfectly OK to
give your front rotors a close inspection for warpage (to eliminate that possibility), the disc caliper isn't sticking
at any part of it's normal travel, the adjustable wheel bearings are adjusted to spec, and last but not least are
the brake pads up to OEM specification...or did the brake shop improve their profit margin by using the
bottom-tier pads that are iffy even when everything else is perfect?

When it comes to brakes, trust but verify. But at the same time make sure you actually need to change/upgrade
the parts already in place *before* you replace them...only to experience the same thing afterwards due to
humid environment/exposed raw rotor interaction.

Try checking to see if you are also experiencing the rusty/not rusty phenomenon, as well as making the
aforementioned checks on the front brakes.

Let us know what you discover.

Cheers --

 

[HotWheelsBurban]

I have a '99 C2500 8-lugger w/JD7 brakes, and after the first couple of stops of the day the brakes are
always absolutely smooth & confidence-inspiring. (This is with recently refreshed rear drums and unknown vintage
front rotors, pads, & calipers from the PO.)

Given this, I do not suspect any front rotor warpage. So smooth that I haven't had any inclination
to measure the runout?

On the other hand, if the truck isn't driven every single day, I do seem to feel something similar to
what you described on the first stop or two. Curiousity piqued, I performed a close visual inspection
of the front rotors prior to driving it one time, and noticed a bit of 'flash rust' on the rotor's friction
faces? But only where the rotor was exposed to the air, for if you moved the truck ~1/2 a tire revolution
you could see that the rotor surface that was underneath the brake pads was still shiny, *not* rusted?

And it seemed that the 'flash rusted' area was indeed more grabby/nonlinear than the smoother unrusted spot.
If you braked at low speeds you could feel the difference as a 'pulsation', not in the pedal, but as how the
whole truck was slowing down. But once the rotors were made uniformly shiny again by the pads (usually
by the end of the 2nd stop) ...all was well, so I haven't pursued any kind of remedy...if one is even possible,
given how much raw rotor surface is exposed to the elements.

And I am confident we're experience similar symptoms, for the problem is absent during a dry spell, but almost
always shows up when it's rainy/humid out.

Then again, on my vehicle the problem has never gotten any worse. But if this symptom is worsening over time
on your truck, this means that some mechanical relationship is changing over time? It's perfectly OK to
give your front rotors a close inspection for warpage (to eliminate that possibility), the disc caliper isn't sticking
at any part of it's normal travel, the adjustable wheel bearings are adjusted to spec, and last but not least are
the brake pads up to OEM specification...or did the brake shop improve their profit margin by using the
bottom-tier jobs that are iffy even when everything else is perfect?

When it comes to brakes, trust but verify. But at the same time make sure you actually need to change/upgrade
the parts already in place *before* you replace them...only to experience the same thing afterwards due to
humid environment/exposed raw rotor interaction.

Try checking to see if you are also experiencing the rusty/not rusty phenomenon, as well as making the
aforementioned checks on the front brakes.

Let us know what you discover.

Cheers --

I have experienced this, particularly on the Burb. Part of it is the front pad lining material, semi metallic so they like to warm up before they stop quietly. And one also should check out the pins and mounting surfaces for the calipers are clean, not rusty, and lubricated with the proper hi temp brake grease. I plan to do this tomorrow on Rawhide since the weather should be much nicer then. Currently in the low 40s here but at least the park turned the water back on.

 

[Hipster]

I have a '99 C2500 8-lugger w/JD7 brakes, and after the first couple of stops of the day the brakes are
always absolutely smooth & confidence-inspiring. (This is with recently refreshed rear drums and unknown vintage
front rotors, pads, & calipers from the PO.)

Given this, I do not suspect any front rotor warpage. So smooth that I haven't had any inclination
to measure the runout?

On the other hand, if the truck isn't driven every single day, I do seem to feel something similar to
what you described on the first stop or two. Curiousity piqued, I performed a close visual inspection
of the front rotors prior to driving it one time, and noticed a bit of 'flash rust' on the rotor's friction
faces? But only where the rotor was exposed to the air, for if you moved the truck ~1/2 a tire revolution
you could see that the rotor surface that was underneath the brake pads was still shiny, *not* rusted?

And it seemed that the 'flash rusted' area was indeed more grabby/nonlinear than the smoother unrusted spot.
If you braked at low speeds you could feel the difference as a 'pulsation', not in the pedal, but as how the
whole truck was slowing down. But once the rotors were made uniformly shiny again by the pads (usually
by the end of the 2nd stop) ...all was well, so I haven't pursued any kind of remedy...if one is even possible,
given how much raw rotor surface is exposed to the elements.

And I am confident we're experience similar symptoms, for the problem is absent during a dry spell, but almost
always shows up when it's rainy/humid out.

Then again, on my vehicle the problem has never gotten any worse. But if this symptom is worsening over time
on your truck, this means that some mechanical relationship is changing over time? It's perfectly OK to
give your front rotors a close inspection for warpage (to eliminate that possibility), the disc caliper isn't sticking
at any part of it's normal travel, the adjustable wheel bearings are adjusted to spec, and last but not least are
the brake pads up to OEM specification...or did the brake shop improve their profit margin by using the
bottom-tier jobs that are iffy even when everything else is perfect?

When it comes to brakes, trust but verify. But at the same time make sure you actually need to change/upgrade
the parts already in place *before* you replace them...only to experience the same thing afterwards due to
humid environment/exposed raw rotor interaction.

Try checking to see if you are also experiencing the rusty/not rusty phenomenon, as well as making the
aforementioned checks on the front brakes.

Let us know what you discover.

Cheers --

^^^ This, I go through this on a newer car with 4 wheel disk every time it rains. If it doesn't clear up in a stop ot two when driving then dig deeper.

 

[Pinger]

Forgot to mention - new calipers on mine also. So, new calipers, rotors and pads and it grabs like crazy when damp/cold. Even in warmer temps the first application of the day is kinda fierce. Just much worse when cold/damp. Once moving I apply light braking with my left foot while driving to clean/heat up the rotors and pads. All good thereafter.
The grabbing is always from the front. The problem I have with the rears is the park brake sticking the shoes to the drums. I (for reasons too tedious to mention) don't like just leaving it in park.

 

[Schurkey]

OEM-style rubber brake hoses? Clamp the rear hose LIGHTLY with a vice-grip. Tight enough to block fluid flow, not so tight that you crush the hose to death.

Understand that your stopping distances are going to be longer. Don't crash into someone.

If it still is grabby first-thing in the morning, it's the front brakes. If it isn't any more...it's the rears.

 

[Dariusz Salomon]

Is it like this when you coming to a stop-truck lurches forward and then you apply more pressure and it stops with kinda seize? Try changing abs sensors-that is what was happening to my Tahoe. Make sure to sandpaper the space where sensor sits-remove any rust-what happens to them-the soace underneath the sensor gets wet, rust builds up and pushes the sensor away, which causes it to misread the speed and brakes grab. Or they are simply damaged(1 or both). Try that before going for new brakes and stuff.