I have a 1996 Ford Ranger, i want to do a engine flush before I start to see what parts can be replaced to improve performance. What's my best option for a brand that will get the most sludge out the engine? She runs fine, maintaining it is my priority.

 

Cooling system or oil?

 

Both would be a great answer eer to receive. I am going to end up replacing the radiator and fan later I have flushed it but only with water it is still a bit murky, any advice is greatly appreciated.