98 Blazer Breaks partially frozen, ABS lamp is on constantly, no trouble codes read. Any advice appreciated.

 

Welcome to the forum!

It depends what the problem is with the brakes. Could be one or more of 7 flex lines that are collapsed, or partially collapsed. Front and rear caliper assemblies are known to have "issues". Caliper pistons, guide pins and mounting brackets like to seize up. Front caliper assemblies, (caliper, bracket & hardware) need to be replaced as necessary, usually every other brake job. The rear caliper pistons are steel and the caliper body is aluminum. As a result, the pistons corrode and bind up in the bore. Rear caliper assemblies, (caliper, bracket & hardware) should be replaced at each rear brake job. The parking brake shoes, all of the hardware, and the cables, need to be maintained on a regular basis as necessary. The parking brake needs to be used on a daily basis, or not at all.

ABS DTC's, (Diagnostic Trouble Codes) can only be viewed on an ABS capable scan tool. If the light is on, there are DTC's in memory. The ABS system does a complete self test at each start up. The speed sensors are checked when the vehicle reaches ~5 mph. If a problem is detected, the light goes on, and a DTC is stored in memory. It will remain there until the problem does not exist, or the memory is cleared with the scan tool.

 

Six months ago, I purchased a 2000 Blazer from a neighbor down the street.

Every now and again, I could smell burned brake pads on the rear.

So I replaced the pads with new ones,and greased everything properly, thinking all would be well.

A trip around the block had the new pads SMOKING HOT.

Up on the jack stands, I couldn't rotate the rear tires.

Opening up both bleeder screws didn't release the brakes.


I took the calipers apart, and found that this 2000 has PHEONOLIC pistons and aluminum calipers. Nothing looked unusual on the insides of the caliper bores , and the pistons didn't have any scratches.

I removed the rubber dust cover and the piston seal from the caliper.

I coated the piston with brake fluid and attempted to push the piston into the bore........ at about one inch, the piston locked hard into the caliper.

I had to use shop air to blow into the caliper to force the piston back out.

Since this wasn't my primary vehicle, and with plenty of time on my hands, I wrapped the phenolic piston with 3M 400 grit wet-or-dry sandpaper and rotated the piston around ten times holding the sandpaper fairly tight around the piston.

I cleaned the piston, re-oiled with brake fluid, and now, the piston would go a little futher into the bore without binding.

At this point, I swapped ends of the piston with the sandpaper and rotated another ten turns.

Several more "sand-and-trys" finally got the pistons where they would go all the way to the back of the caliper and would come out with a tug of my finger with no binding.

CAUTION !!! What I am describing is a gentle polishing of the piston....
I had 400 on hand, but would have used 600 if available.

When I finished, the piston was a uniform brown phenolic color ...

When it was binding, the surface was blacker and was probably glaze from years of high temperatures.

I installed new dust covers and piston seals ( $4.89 from Advanced Auto ).

That was almost four months ago, and the brakes are performing very well.

No more binding and no more brake smell, and just as importantly....
no brake fluid leaks.

Gas mileage went from 16 to 19, and testing on a rain slick parking lot
( always test your brakes after repairs ) shows excellent braking.

DISCLAIMER :

I'm not recommending this procedure to anyone.

It was a personal decision on my part to EXPERIMENT with MY personal vehicle. I just wanted to UNDERSTAND why so many people who own Blazers have so many problems with the back brakes. I know how things "should" work, and that if rear brakes are binding..... something is wrong.

 

Most auto parts stores sell remanufactured assemblies that include the caliper, mounting bracket, guide pins and clips. Usually run ~$45 each and it takes about 10-15 minutes to swap & bleed.