1999 Toyota Camry

Other Category problem
1999 Toyota Camry Engine Size unknown Wheel Drive Type unknown Automatic 90,300 miles

I live on a dirt road, in the country. After drving my 99 Camry for awhile, there was this rattling sound coming from the front end of the car. It sound like my tires could fly off any minute! But my car doesn't shake, bounce, or rattle with the sound. I had gone to get my oil and oil filter changed, and on my way home the brakes made a loud screeching noise. So my step-dad changed the brake pads to find they were cracked. This was a week ago. The sound had stopped, but is back, but even worse! My car doesn't shake with the sound, and it definately comes from the area about the tires. And it's a lot louder on uneven surfaces. We've asked several people of the problem, some suggest dirt in the brakes, other suspect that my bearing need to be cleaned and greased. What do you think?