I drive an 07 king ranch with 83k on it. I went to change my coolant today and once drained, I noticed a thick orange sludge in the cold fill reservoir. I removed the reservoir and flushed 95% of it out. What steps can I take to remove all the other old coolant? My guess is that the previous owner somehow mixed green and orange antifreeze based off Google searches. I put orange coolant in today based off the fact that all the fluid I removed was orange. What steps can I take to remove this junk from my cooling system?

Thanks in advance

 

Get you a good flush and flush the system.