We had to replace our radiator in Sep 2017. It had leaks in three of four corners. We had a new and much higher quality radiator built by
https://radiatorsupplyhouse.com/ located in Sweethome, OR. The original radiator was aluminum and weighed about 150 pounds. The new radiator is steel, brass and copper and weighs about 250 pounds. Our radiator not only performs engine coolant cooling, but also a small section did transmission (I think) oil cooling. The cost of the new radiator was over $4,000 delivered to Eagle Freightliner at Hermiston, OR. Interestingly, a replacement aluminum radiator was almost the same cost and is made in Louisiana (I think).
While in there with the leaking radiator removed, be sure to leak test the Charge Air Cooler, check the fan bracing for cracks and check anything else while it's easy to see and repair/replace.