ACK! Something let go in the brakes.

[KShortell]

I went to drive the Chevy to work today. Yes, she's still a semi-daily driver. Well, I got to the end of the block and went to hit the brakes. I thought I heard a pop or clunk and then the pedal went halfway to the floor. The brake warning light came on. Well, I turned 'er around and parked back at the house. I ended up driving the Jeep to work today.

The front half of the master cylinder is dry. The rear is low, but not sucking air like the front.

I've just been out in the dark with the flashlight looking over every inch of the brake lines; I found no wetness at all. I seem to find that leaks and such seem to show up better at night with a flashlight or worklight. Nothing apparent showed up in daylight earlier today, either.

I replaced the calipers, hoses, and right front steel line up front three years ago. The rear steel line (frame-mounted) was replaced last year.

My worry is that, in the absence of any external leaks, the master cylinder may have failed. The FSM and Haynes manuals that I have don't really give a great "real world" description of what it feels or sounds like when this happens.

So, any thoughts? I'm thinking of letting a shop tackle this one. I've got too many social events going on this month. I love my truck and get great satisfaction out of doing my own repairs, but the girl-chasing opportunities have to come first!

Thanks for your input!

Kevin
'86 Chevy Suburban C10 Silverado
350 SBC / TH700R4 / 3.73 / P235/75R15XL factory drivetrain