Rear disc brakes in my 99 LS 2wd 4dr wouldn't relase all the way. I did some research here and found some things I'm going to try like cleaning the pistons in the calipers, the slide pins, and cheking the brake lines going to the calipers for internal damage. Some of the suggested fixes seem to assume that only one side at a time had a problem. What are the odds that both sides had a problem at the same time? I've already replaced the rotors and brake pads and it's still the same on both sides.

 

Are you sure that it is the calipers and not the internal drum parking brake?

Also, if it is both sides, are the slow to release or that they just always drag? If they are slow and maybe even if they always drag, it may be the flex line that goes from the frame down to the axle. If the flex line has swelled internal to the casing, it can restrict and/or cut off flow out of the calipers.

 

Unfortunately they just don't relase all the way. Even with the new pads and rotors you can feel the resistance at take-off, smell them getting hot after a short drive and the wheel heats up to a ridiculous temp. That flex line sounds like a fit for the symptom.I figured that the odds of both calipers failing at the same time were low so there had to be some component that both rear calipers shared. Thanks for the response!

 

Did you grease the slides for the pads good. I know when I did my fronts and rears they had basically only brake dust left no grease. When they were like that they dragged.

 

Update - I took the calipers loose yesterday aftrenoon and found that the dust boots that protect the caliper piston were cracked and had holes in them. I tried to compress the caliper with a C-clamp (while disconnected from the brake lines) and it would not compress all the way. Looks like I'm buying new calipers. Fortunately the piston side of the calipers can be purchased seperately and are only around $50 each when you bring your core.

 

A cracked boot can allow all kinds of gritty stuff in there, possibly seizing up the piston. Sounds like you have found the problem. It is odd to think that this would happen to both sides at the same time...

 

I had a similar problem with the front, but it was only one caliper that wouldn't release. It was the flex line that had went bad and wouldn't release pressure. So I replaced all my flex lines with some nice braided ones from summit. Problem solved.