Steaks are tender and tender meat should cook over high heat. A trick to locking in flavor and juices is to sear the steak.
I usually build an extremely hot fire when grilling steaks. I like my steaks with a nice char on the outside and medium to medium rare on the inside.
Build a pyramid shaped stack of coals and let them burn down. When the coals are mostly white the fire is ready.
I place the steak directly over the hot coals for 1 minute per side. The flames may engulf the steak, but this is okay. The high heat is sealing the outside of the steak.