Rich,
10% is normal wear for an older motor,hell 3% is normal for a mass produced engine! I'd take what the Ford mechanic said with a little suspicion. There are 2 ways to tell if a bearing is worn; 1 - is take a sample of
oil and send it out to a lab to get anilized for what metal particles are in it. 2 - Take the motor apart and main and rod bearing out and inspect them. There is no other way to tell if the bearings are worn unless it's hammering like a sledge hammer.
Good Luck,
Perry.
