Okay, I have searched and searched and searched and I haven't found anyone that had my particular problem and how to fix mine. Long story short what started out as a rear brake pad replacement has turned into a whole new braking system minus ABS module and brake booster. First I changed the master cylinder because the brake shop had told me that it was toast. Secondly I changed the rear brake pads and then my calipers stuck and I ended up having to change them both on the side of the road because they were smoking.. I put the new calipers on the back and the back was still not working properly they were my rims were still getting hot so I believed I had maybe a collapsed line in the brakes so I replaced all four soft lines. (I skipped the rear middle line and still have it to replace) so after the brake line replacement the rear brakes started doing fine for a bit and then all four wheels started acting up and getting hot . So I went ahead and changed the front calipers out also put new calipers on the front greased the pads the slider pins are greased put everything back together my rear calipers seem to be working correctly no Hot Wheels. My front brakes are still sticking for some reason. My parking brake light and ABS light are both on if I'm driving the Blazer and the brake light being on I smashed the brake pedal quickly and the e-brake light went off but then again came back on once applying the brakes. I have replaced the master cylinder all four calipers all of the brake pads all four rotors and four of the soft brake lines my front brakes are still sticking and I'm about to pull my hair out as to why
Anyone have any type of answers for me I appreciate it thank you

 

Not sure if it is the same, but when my dad had our 96 Sierra, which has many of the similar parts to the blazer, he had trouble with the calipers sticking. It was found, at a shop that the abs unit was failing, If you've replaced all that but NOT the abs unit, maybe it's an issue.

 

I would first isolate the problem to either the calipers or the hydraulics up to the caliper. Raise the vehicle on a wheel that is dragging. Spin the tire by hand to confirm that the brakes are engaged and dragging and then release the fluid pressure at the bleed screw and see if the wheel loosens up and rotates more freely. If so its the hydraulics upstream, if not, its the caliper, pads, guide rods, etc.

Then we go from there.


George

 

Hey GeorgeLG,
All right I'm going to try and discuss this in plain English or you can understand it cuz sometimes I have a hard time explaining particular things but here goes I raise the vehicle I ran it down the road and got my calipers hot and the wheels are dragging there I can spin it and they'll rotate maybe one time before they stop on their own I opened the bleeder valve on the wheel and there was no change fluid came out. I took it down the road again and got them warm again came back jacked it up they're dragging same as before I cracked a line near the front of the Blazer on the master cylinder only a few drops of fluid came out no change in the wheel then I bled the rear connection on the master cylinder no change on the wheel my rear brakes are doing fine it's only in my front brakes. And I wasn't even having a problem out of my front brakes whenever all this started because I was replacing my rear brake pads and everything started locking up on me. My front brakes were doing fine when I started this initially

Can this connector ever go bad in the ABS module?

These are the two lines I bled forward first then aft

Can this unit be taken apart and sprayed down with contact cleaner or is it just the connector in the front

 

Sorry for having to add this here but I couldn't figure out how to to add it to the original post..

 

A dragging brake that is not relieved by cracking the caliper bleed screw implies a caliper problem but a soft pedal while running and the brake and abs lights on suggested problems up at the firewall or in module communication. If you do not run the truck first, do the brakes drag and if they do is it relieved by cracking the caliper bleed screw while they are still cold? Maybe your heating them up as they drag from a problem at the firewall and now they mechanically drag at the caliper from overheating.

Has anything been done to the master cylinder, brake booster or ABS system? Did the brake fluid run low during any of this causing a potential bleeding problem with the ABS system? Do you have evidence of a vacuum leak?


George

 

The master cylinder has been replaced so it's brand new brake booster is not been replaced nor has the ABS module. I replaced the master cylinder because I was going to change the rear brake pads and I looked in the master ceiling in the reservoir and that was a bunch of trash and it was a crack in the top of it so I went and bought a new one and I blew out the lines with air from the master cylinder to each wheel. That's probably where I went wrong. Probably shouldn't have done that. But I was trying to be sure the lines were clear of debris. When I get to the vehicle and it's been sitting like overnight I can get in it and drive it for about say 15 minutes and it starts affecting engine performance it starts dragging causing me to have to press the gas harder and also when I have it cranked and I press on the brake pedal up and down up and down it messes with my vacuum makes my idle speed fluctuate. As far as jacking it up when it's cold and seeing if they are dragging I have not checked that but I can and will before I put the master cylinder in I pumped it until fluid came out so I guess pretty much I bled that of the air I don't know if I have air in the ABS module from blowing the lines out I don't know as far as vacuum leaks I don't think I have any the one line that I did find open I couldn't tell where it went so I plugged it and the other two go over there supposed to as far as I know actually a mechanic at a shop plugged it cuz I guess he didn't know where it went. And I really can't say 100% that the brakes were fully operational beforehand ABS light has been on since I had it parking brake has not worked since I've had it but the brake light coming on is a new occurrence I think I just opened a can of worms whenever I started messing with the rear brake and it's been a in series sequence ever since

 

OK, I went back and read the whole story. There is a lot going on here. No judgement, your learning and taking initiative but we need to slow down and tackle all of this one at a time. First, don't take it for a test run before checking for dragging brakes, this may be complicating things. Do the cold dragging test on stands then relieve pressure at the caliper bleeding screws and see what happens. That said, if all 4 brakes are dragging then its probably not the calipers unless the same error or bad parts sit in each corner which is not the most likely. Did you check for smooth caliper movement over the guide pins before installation? On my last caliper install the guide pins were not parallel and required some "finessing". If you get relief at the caliper bleeding screws that will take us to the firewall.

Forcing air through the system probably pushed air into the ABS system which needs either a high end scanner to bleed or the gravel road trick..

You had open vacuum lines and capped things with out knowing where they are going and you show signs of a vacuum leak. This needs to be resolved, there re many threads with diagrams here. Christine has the best one.

Did you bench bleed the master cylinder?

That leaves the master cylinder pushrod clearance and the brake booster which we may need to address.


George

 

I am on my way to where blazer is being berthed at this time... I will update shortly. Thank you for the direction..

 

Since you have to travel to work on your truck, here is the first test at the firewall if it looks like it’s the hydraulics:

Loosen the master cylinder about 1/4” from the brake boost and see if the brakes release. If so then it’s something between the boost cylinder and the pedal/stop switch. If not then it’s the master cylinder to the calipers.

you may need to pump the brakes first to get them to lock up and/or start the truck and repeat since it sounds like there my be a vacuum component/brake boost component to this


George