When it rains and my truck sits over night the brakes lock up with the slightest touch of your foot when you first get in the truck.

Over the summer I had some vibration under braking at slow speeds so I serviced the front brakes, new pads/hardware and new rotors. When i was in there i found one of the guide pins was shot, the rubber boot had split and there was all sorts of nasty corrosion in there so I got a new pin cleaned everything up and the brakes worked great until recently.

There is no evidence of caliper sticking (no evident fluid leaks, no pulling under braking, no excessive heat or dust on one side). The only symptom is that the brakes will lock completely after it rains. As soon as you get up to speed and put some heat into them they function normally again.

Anyone have any ideas?

 

I removed my front ABS and mine does the same. After a few minutes they are fine but it takes a few stops. Do you have ABS?

 

Yeah i have ABS, it feels like its a mechanical problem, like something sticking but theres no visual evidence if you take it apart. Could be ABS i suppose, no malfunction light or anything tho

 

Common problem with vehicles with drum brakes when they get wet. Only true way to fix the problem is to convert to disc brakes in the rear or just kinda ignore it.

 

Are front or rear brakes locking up? Or both?

 

yeah im familiar with the drum brake issue, unfortunately these are the front brakes locking up. I've determined this by driving backwards stepping on brakes-no symptom, where as drive forward step on brake-lock up. Plus you can feel that its coming from the front.

I'm thinking caliper's going bad. Does anyone have tips for confirming this before ordering new ones? Like i said visually theres no leakage or excessive corrosion on the piston or damage on the rubber surrounding it.

 

Idk but if you saw corrosion on the pins mostly the caliper has some to. Sometimes its hard to see it.

 

Also has the fluid ever been serviced? It does degrade over time and can trap moisture the heat would then evaporate that moisture. Its a long shot and relatively rare that that happens but worth testing there are test strips you can get from the parts houses to determine its age.

 

That sounds like a possibility to me. I'll see if I can get some of those strips. The fluid is original 100k miles. Thanks

 

No problem i also see your in Connecticut i did a brake job on a Michigan based mustang that the lady brought to Georgia the piston compressed ok but it came back a few days later apparently whatever corrosion was inside the caliper was broken loose when the caliper was compressed for the brake job and got stuck in the lines and there were no outward signs of corrosion so if the fluid is holding water you may not see the corrosion. Good luck on your search. Hope the info helps.