Front caliper staying applied 2 different trucks

[313C10]

just my luck this is happening on both my trucks at the same time the first is an 86 4x4 blazer the second is a 84 c10.The blazer is worse got a caliper for that, and putting it on now i dont really have experence with brakes exept air brakes. as for the c10 the rubber in the res. was getting sucked down i replaced that, still nothing it seems like if it sits for a while  it will push brake fluid through the resivoir and release. Any ideas im kind of lost and i cant farm it out. both have fluid and no kinks or leaks in lines.

[1982 Daily Driver]

Check the rubber lines going to the calipers, after time they deteriorate on the inside and work like a check valve not releasing the pressure after the brakes are released.

[313C10]

repalced the caliper on the blazer and it seems to be good now onto the c10

[bake74]

      Can you say "murphy's law"  Both rigs at the same time, same problem.  You are having a bad day my friend.

[313C10]

daily driver good call it was the brake line.replaced caliper also. any body ever replace the porportioning valve thinking about doing that for the heck of it

[1982 Daily Driver]

I'm glad I could help. I think a new proportioning valve is expensive for something to change for the heck of it. I have never herd of one going bad.