One problem related to radiator has been reported for the 2005 Ford Ranger. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2005 Ford Ranger based on all problems reported for the 2005 Ranger.
Loud squeal for several days thought it was tension pulley. That was replaced with no change. A few days later going down the road. A very loud squeal from the engine area and smell of burning rubber. Later was determined the vibration dampener had come apart. The rubber had come part allowing the groove section the belt rides on to slip toward the back up against the front cover. In looking online for information it was discovered this is a common problem with explorer and Rangers with the 4. 0 engine. A lot occur with low miles on the vehicle and some result it major repairs as the pulley flies off taking out the radiator. I was able to replace mine because I am a mechanic and have the tools to do the job. So my repair bill was not as much as others had stated.