2003 Mazda 6 caliper partial lock then release

[xracerx13]

wonder if this ever happened to anyone. I did my pads and rotors front and rear. been driving the car left and right for 2 months. All of a sudden 2 days ago my right front caliper was partially frozen. I noticed after a half mile on the Expressway. Car was shaking and it stunk and I obviously saw smoke when I pulled over. So I put it in reverse and it fixed itself. Took it up to Mavis today cause I wanted it on a lift and they said the caliper was fine. No explanation why it happened or if it would happen again. I have been driving the car and not hitting the brakes to get the caliper replaced. When I saw the guy put the tire back on I was stunned. Story was that it could happen to new pads. I was like. Dude I drove to Canada and back. Syracuse and back like 10 times and to work every day 35 miles round trip.
ANY one know what the hell could have happened? I know it will happen again. Can't be air cause the brakes are tight. Maybe a proportioning valve issue?

[Steve Wood]

Make sure the calipers are floating properly and the bolts/pins are clean and lubed.

Second thought is that the hose collapsed momentarily and the fluid did not back off so the caliper could not let go

[nocooler]

Abs? When was the last time the fluid was flushed?

[xracerx13]

No ABS. Fluid was flushed recently.
The calipers are floating properly and the bolts/pins were cleaned and lubed. I made sure of that.
I talked to someone last night that told me that the hose may have collapsed internally. What would cause the hose to collapse momentarily?

[Steve Wood]

Age, flex, high temperature cause the inner liner to separate from the outer with time.  Then when you step on the brake, pressure pushes past the collapse and applies the brakes.  When you let off the brake, there is no pressure in the opposite direction so that the fluid stays locked into the caliper and the pads cannot release from the rotor.  You were lucky that it released...alt ho I would expect it to still be dragging to some degree.  It won't last if that is the case.

It's very common with age and the lines should be replaced on any car after ten years or so as a precaution.

[xracerx13]

Believe it or not there's no drag, no smell, no warpage thank god, but I have not hammered the brakes yet to find out if it will do it again..

[Steve Wood]

I suspect it will do it again

[xracerx13]

Ill swap out the brake hose and take if from there. Thanks

[jonasterg]

Dumb question - did you use the right lube on the slide bolts?  Years ago I used a petroleum-based lube (not paying attention)... rubber boots on the slides swelled up slowly over a few months.  New boots & cleaned up the slides, problem solved.

[xracerx13]

Tried a new hose and it didn't do the trick. Had to put in a new caliper. Problem solved.

[Steve Wood]

Glad it is working right!