Hondobob

My right front caliper locked up while driving. I replaced it and it worked fine for a year (in frequent use). The new caliper started intermittently locking up now. I also get a noticeable hissing sound coming from near the brake pedal...like air leaking out. Not sure how the power assist works on these (PFM: pure F magic?). Brake pads fine and so is fluid level. Hoping to do myself...the ol girl hasn't been to a professional in over 10 years...

joe mcmillan

Could be the hose to that caliper. They sometimes break down inside and don't allow the pressure to release immediately. That's where I would go first.

Hondobob

good idea. if that's it, hope it didn't contaminate caliper. tomorrow will check how hard it is to replace for an amateur.

any ideas on the air / hiss by the break pedal? Still hisses sometimes when foot is just OFF the pedal. Thanks!.

Cryptyx

I got a constant hissing noise while driving my bronco due to a vaccum leak in the brake booster once. Hope that helps lol

Hondobob

inside the cab where the brake pedal linkage goes thru the floor, there is a plastic piece (back of vacuum component which under hood has master cylinder mounted on it) that started to breakdown with age...several cracks allow air leak and hissing noise. I slapped some RTV on it until get the money to replace.

Brakes work fine after replacing the old caliper HOSE.

Thanks to all.