The mystery has been solved. I just took it to the local mechanic near home and he confirmed that the left rear caliper is stuck on and the pads wore down completely. It needs a new caliper, rotor, and 2 sets of pads. He even said it was likely the reason why the brakes failed in the first place because the brake fluid could have boiled and caused the brakes to get softer and softer until the brakes finally nearly had a near total failure. It was likely the reason why they failed again 200 miles later since the brakes could have cooled down while it was on the tow truck and performed properly again leaving no evidence of a problem. All of you can see where I am going with this. The master cylinder was not broken in the first place. The caliper got stuck, caused the brake fluid to boil, probably left air in the system and caused the brakes to fail both times. The shop in Jersey made a false diagnosis and repair and they lied when they said the master cylinder was leaking out the back and they are probably going to use the master cylinder to fix another Blazer and pass it off as brand new. This now makes me wonder what type of master cylinder is in my truck now.

 

Ok, I had the rear left caliper, rotor and a new set of pads for the rear axle done on Wednesday near home since I knew that the truck would not go more than a couple miles with the caliper stuck like it was. Then I did 250 miles of driving upstate and back. The pedal did feel a bit soft, but the brakes work just fine and I was able to make that trip upstate to do what I had to do before Memorial Day Weekend. I went to start the truck 5 min ago and as soon as I released the parking brake, the headlights turned on like they were supposed to, but the BRAKE light didn't turn off. It is just on no matter what I do. I tried cycling the brake pedal and no luck. The light is just there and won't turn off. I didn't leave the house because I was concerned something else could fail. What would make the light turn on after the truck was parked for 24 hours? The brake fluid is full. It was not on after the caliper replacement and it was off for the trip upstate and back Wednesday and Thursday and it was not on after that until I started the truck a little while ago. The light didn't show up at all since last weekend after the brakes failed the 2nd time (see my previous posts) and I had to have it towed again to the same shop in NJ where they started working again. Is it possible there is air in the system or the switch went bad and that is why the light seems to be stuck on? Where is this switch for the warning light located and can it be replaced easily? I am honestly afraid to drive this truck now after all this. When I have the brake light checked out, I am going to ask if there is anything else on the brake system that might be close to failure because I don't want to lose my brakes and have to call a tow again. Last week was the first time I ever had to call a tow truck for this truck and I am frustrated because I had to do that.

 

The warning light being stuck on after being parked for 24 hours- does that mean I STILL have a problem or is the switch just broken and I can drive the truck? Is the switch hard to replace?

 

Hey everyone. I think alot of you have seen my thread "Brakes failed on highway", but now I have a related but different issue. I went to wash my truck before and the right rear wheel (the LEFT rear was the one that got the new caliper and rotor and pads 4 days and 300 miles ago.) started to just make thick white smoke as soon as the water hit it. The water just boiled as soon as it hit the rotor and wheel and the smoke went higher than the truck. It was NOT doing it with the other wheels (including the fronts and the other rear one with the new caliper). Is this normal with new pads with the original caliper or should I have that looked at? It was really hot and I almost burned myself. Could this mean that this caliper is sticking and the same thing will happen to this one as the left one (with the left one, the caliper stuck, the pad wore out all the way down to the metal and it started making scratching noise. I had the caliper, rotor and pads on both rear wheels replaced. This likely caused the 2 brake failures last weekend in NJ because the brake fluid likely boiled due to the stuck caliper. The shop in NJ where I had the truck towed to made the mistake of calling it the master cylinder and replaced that and didn't even check the calipers.

 

I moved this from where it was as it is definitely related.

If you had a sticky caliper and it was replaced, and the new caliper seems to be sticking as well, I would suggest looking at the actual brake lines coming from the T in the back. It almost sounds like your LR brake line is clogged or something and not allowing a brand new caliper to operate correctly.

I know it's frustrating, try to be patient and work things out one at a time.

 

Sorry about the mistake with the new post. It isn't the new caliper that is sticking. It is the other one that was not replaced that seems to be very hot, but did receive new pads but nothing else. The system has also been bled and flushed 3 times in the past week.

EDIT: Just as a side note, when I throw in all the computer systems and modernize the interior of this truck, maybe I should throw in a brake temperature monitoring system to prevent future problems like what happened because I could have prevented all this if I knew they were dragging!

 

If the other caliper isn't sticking, I would look into physical problems, i.e. something rubbing the rotor. I think you mentioned the parking brake was checked and adjusted?

 

Is it possible that when the rear left rotor got stuck and caused all these problems, it did something that could damage the right rear rotor? It is the right rear wheel that is the problem. The left rear was the caliper that failed and allegedly caused both brake failures when the caliper got stuck and made the brake fluid boil. As I said, I already had the left rear caliper, rotor and pads on both rear wheels replaced. I never mentioned the parking brake at all. I did have to use it once to stop the truck once it got to a crawl once the brakes failed and I had to avoid a crash. It seems to be releasing properly, although I have to push the parking brake pedal to the floor to get it to hold the truck. Should I not drive the truck until it is fixed?

 

If the parking brake pedal goes to the floor to engage then I would say it's worth looking into.

 

What would that have to do with the hot rotors and wheels? It was like that after the caliper on the left rear wheel was replaced. Aren't the parking brakes a separate assembly that have nothing to do with the regular hydraulic brakes?