I have a 2000 Ford F-250 Super duty V10 6.8L, that is knocking. Anyone know what it could be?

I have a 2000 Ford F-250 Super duty V10 6.8L, that is knocking. Anyone know what it could be?

KNOCKING? Could be a bad rod bearing, could be too much timing or too low a grade fuel (octane). Depends on what's actually knocking.