I've got an 06 SR5 4x4 V6. I've had it for 6 problem free years and it has 99K miles. My wife drives it mostly. Twice in the past 2 weeks, she has said that the vehicle won't stop. Both times, she has been driving at low speeds and slightly turning right. She said that the whole car "shakes" and the vehicle won't stop. She thinks that the brake pedal is pulsating, as though the ABS is kicking in. I asked her if any lights on the dash were lit and she didn't look. I've driven it more lately and have found nothing wrong. We've had this car for 6 years and she's never said anything like this has happened in the past. She said that it "shakes" violently and that it rolls about 10-15 feet before it stops. It drives perfectly immediately after and everything seems fine. Any ideas?