History/info:
2001 jimmy, 4x4, 4 door, slt (I think), with about 149000 miles on it.

I replaced the rear discs/pads last summer. This summer, I replaced part of the rear brake line, from a little ahead of where it splits for the rear axle, at a fitting, and then splicing it in a little in front of the rear wheel well.

Current problem:
There sounds like either a pump is spinning without resistance, or like something is grinding. However, it only happens when slowing from ~10 mph down to stop. And only after driving for about 30~45 mins/15~25 miles.

Any ideas of the culprit? I havent had a chance to pull anything apart yet, but any suggestions of what I should look for when I do?

Thanks

 

sounds like a sticking caliper best to inspect it see if the pads are worn and if the rotor is chewed up


also any abs light on ?

 

rusted backplate or damaged e-brake rubbing on the rotor ?

 

@xgiovannix12
The ABS and the parking brake warning lights both come on at random times (although mostly when it is wet out). I think the ABS light may have come on one of the times the brakes did that. If the caliper was sticking, would it feel harder to push the pedal down?

@98blazin
Is the backplate a non-structural, sheetmetal plate (looks like a dust shield on the inside)? If it is what I am thinking of, they have mostly rusted away.

 

sounds like your abs is activating its self read this link over

https://blazerforum.com/forum/tech-a...ment%5D-26941/

 

im not sure what you mean by ''a pump running'' or ''grinding''.
but, if your brake pedal vibrates/pulses between 5-10mph to zero, thats a false abs activation due to dirt/rust between the hub and the abs sensor.

the backplate/dustsheild is the same for me. its the plate behind the rotor.
mines are also rusted away but a peice was hanging down and rubbing inside my rotor causing a weird noise. if your brake pedal does not pulse when slowing down to a stop, abs is fine and you probably just have something inside your rotors/drums making noise...

i hope it helps !

 

From what it has felt like/from the descriptions here, I'll be looking first at the abs sensory. Would another symptom of this issue be that the speedometer does not move smoothly? B (sometimes it moves in a jerky fashion)

Thanks