454 broke pushrod inside

[sbc10guy]

Hi guys i started up my truck at work last week and it was making a chirping noise. I drove it home and took the belts off one by one with no difference. i listed very close and it sounded like it was coming from the pass side valve cover with a tick as well. I drove it to get an alignment and back and by this time it was making the chirp along with a grinding almost dog bark like sound. I pulled the valve cover and noticed the number 2 lifter was bone dry and looked almost burned. I pulled the rod and about an inch was missing and it was crumbling like a cookie at the bottom. If i change my oil right away what is my chances of the motor going in the near future due to bearing wear/chunks getting into the oil pump filter? A side note, removing that broken rod took away all the noise it was making.