1991 Camry (Gen 2) 4-cyl (3s-fe), auto, US assembled.
At the end of a 90 mile drive today I heard a knocking when I slowed down. It sounded similar to a bad CV-joint knock, but I don't think it was the CV. It only happened while braking (Straight or turning while braking). It didn't make the noise when turning in either direction. Only when braking. It was a heavy clanking sound that slowed down as the car slowed down.
When I drove home 6 hours later, the noise had disappeared.
I took both front wheels off and everything looked fine. Calipers and pads were fine. No signs of fresh metal wear. The only thing I could do to elicit a similar sound was when I rotated the lugs back and forth and made the disk clank against the studs. (The holes for the lugs in the rotor are a bit bigger than the diameter of the studs.) The lug nuts were on TIGHT, so I don't think that had anything to do with it either.
Any ideas???