Strange Clunk in the Brake Pedal

[rhb1963]

I've got an "04" XLT with 46k on it and had the brakes serviced at the dealer about 2k ago. Just recently I've developed what I can only describe as a "clunk" in the pedal when I sometimes have to brake a bit hard (has only happened 3 times but does not seem right to me). It feels like someone is hitting the pedal with a hammer from the opposite site right before the vehicle comes to a stop.

I'm wondering if it's like a piston getting hung up in a caliper and them braking free or something in the master cylinder doing the same or am I way off.

Any help would be appreciated.

[fireball0012]

My best advise is to take it back to the dealer and mave them fix it. It should have a least a 6k warretry on the brake job.

[jr78]

Sounds like the ABS. Could be normal or an ABS misfire caused by a bad sensor or broken tone ring.

[rhb1963]

It actually feels like 2 pieces of metal getting stuck as they pass each other then braking free with a pop or clunk (not a pulse like normal ABS action). Happens intermittently but I'm affaid it could lead to a catostrophic failure in the system somewhere down the line.

[jdub4802]

i Have a 2004 ford explorer xlt v8 4.6L 4x4. and i have this same issue. i turned the rotors and installed new pads and i still have this issue.. not sure what it is, it only does it if i do a hard brake, and sometimes when i slow down and turn into a drive way... It feels exactly how you said, any answers?

Thanx

[rhb1963]

I took it to the dealer and they test drove it with me in the passengers seat and couldn't replicate the problem. Then They checked the brakes and still found nothing.
Up to this time it still does it and I can't figure it out.

[KU40]

check to see if your driveshaft has any play in it at the rear differential. I think my differential has a little looseness in it, and sometimes when I brake or release the break I can feel it give a little thunk as it disengages or engages again from shifting.